Upsala J Med Sci 88: 141-149, 1983 

What Do Patients Know About Their Digitalis? 
A comparison between two different areas in Sweden 

Kurt Boman,' Hans Mollerberg' and Jan-Erik Ogren3 
From the 'Department of Internal Medicine, 'Central Laboratory, and 

'the Pharmacy of Skellefieii Hospital, Skellefteii, Sweden 

ABSTRACT 

O u t  of 1183 u n s e l e c t e d  o u t - p a t i e n t s  i n  S k e l l e f t e a  and 620 i n  U p s a l a ,  200 

p a t i e n t s  from each p l a c e  were s e l e c t e d  a t  random t o  b e  s e n t  a q u e s t i o n n a i r e  

on t h e i r  m e d i c a t i o n  w i t h  d i g i t a l i s .  Answers t o  t h e  q u e s t i o n n a i r e s  were ob- 

t a i n e d  from 196 p a t i e n t s  (98 p e r  c e n t )  i n  S k e l l e f t e d  and from 163 p a t i e n t s  i n  

Upsala ( 8 2  p e r  c e n t ) .  About 8 5  p e r  c e n t  s t a t e d  t h a t  t h e y  took t h e i r  d i g o x i n  

a s  p r e s c r i b e d  o n c e  a day. About 60 p e r  c e n t  knew c o r r e c t l y  why d i g o x i n  t r e a t -  

ment was g i v e n  and 2 0  p e r  c e n t  were u n c e r t a i n  a s  t o  why t h e y  t o o k  d i g o x i n .  

About 4 5  p e r  c e n t  s t a t e d  t h a t  t h e y  f e l t  improved t h a n k s  t o  t h e  d i g o x i n  t h e r a p y .  

55 p e r  c e n t  d i d  n o t  know a b o u t  d i g i t a l i s  s i d e - e f f e c t s .  About 50 p e r  c e n t  de- 

n i e d  h a v i n g  r e c e i v e d  any i n f o r m a t i o n  a b o u t  d i g i t a l i s  and 50 p e r  c e n t  were un- 

s a t i s f i e d  w i t h  t h e  i n f o r m a t i o n  t h e y  had been g i v e n .  Only 1 5  p e r  c e n t  were con- 

t e n t  w i t h  t h e  i n f o r m a t i o n .  Methods f o r  improving t h e  i n f o r m a t i o n  t o  p a t i e n t s  

a r e  p r o p o s e d .  

INTRODUCTION 

S e v e r a l  s t u d i e s  h a v e  d i s c l o s e d  t h a t  o u t - p a t i e n t s  know v e r y  l i t t l e  a b o u t  t h e i r  

d r u g s  and f i n d  i t  d i f f i c u l t  t o  comply w i t h  t h e  c o n d i t i o n s  o f  t h e  p r e s c r i p t i o n  

( 1 , 6 , 8 ) .  Due t o  t h e  n a r r o w  t h e r a p e u t i c  r a n g e ,  i t  i s  p a r t i c u l a r l y  i m p o r t a n t  

t h a t  t h e  p r e s c r i b i n g  o f  d i g i t a l i s ,  o n e  of t h e  d r u g s  most commonly p r e s c r i b e d  

f o r  e l d e r l y  p e o p l e ,  is a d h e r e d  t o  c l o s e l y .  Two B r i t i s h  s t u d i e s  ( 9 , l O )  showed 

t h a t  a b o u t  h a l f  o f  t h e  o u t - p a t i e n t s  d i d  n o t  t a k e  t h e i r  doses of d i g i t a l i s  

e x a c t l y  a s  p r e s c r i b e d .  The p u r p o s e  o f  t h i s  s t u d y  was t o  f i n d  o u t ,  what 

p a t i e n t s  i n  a s m a l l  town ( S k e l l e f t e d )  knew a b o u t  t h e i r  d i g i t a l i s  m e d i c a t i o n  a s  

compared w i t h  p a t i e n t s  i n  a u n i v e r s i t y  c i t y  ( U p s a l a ) .  

141 



PATIENTS 

During t h e  t h r e e  months, J u l y  t o  September 1978, 1345 p r e s c r i p t i o n s  o f  d i g o x i n  

( L a n a c r i s t ( R ) ,  Draco) were made up a t  t h e  pharmacy o f  S k e l l e f t e . 5  H o s p i t a l  and 

t h e  pharmacy ( N o r d s t j a r n a n )  i n  S k e l l e f t e . 5 .  T h e s e  p h a r m a c i e s  s e r v e  an a r e a  w i t h  

40 0 0 0  i n h a b i t a n t s .  Out o f  t h e s e  1345 p r e s c r i p t i o n s  1183 c o u l d  b e  u s e d  t o  i d e n -  

t i f y  p a t i e n t s  e l i g i b l e  for t h e  s t u d y .  T h e r e  were 678 f e m a l e s  and 505 males. A 

random sample o f  250 p a t i e n t s  was t a k e n  from t h i s  p o p u l a t i o n ,  and 200 o f  t h e s e  

p a r t i c i p a t e d  i n  t h e  s t u d y .  The 50 e x t r a  p a t i e n t s  were u s e d  i f  some of t h e  f i r s t  

2 0 0  p a t i e n t s  had moved, d i e d  or c o u l d  n o t  be found. T h i s  was t r u e  f o r  1 0  

p a t i e n t s .  The 2 0 0  p a t i e n t s  p a r t i c i p a t i n g  i n  t h e  s t u d y  were randomized i n t o  t w o  

g r o u p s :  t h e  A g r o u p  w i t h  56 f e m a l e s  and 44 males and t h e  B g r o u p  w i t h  71 fe- 

males and 29 males. 

I n  t h e  U p s a l a  pharmacy (Kronan) 671 p r e s c r i p t i o n s  were h a n d l e d  d u r i n g  t h e  same 

p e r i o d  as i n  S k e l l e f t e H .  6 2 0  o f  t h e  p r e s c r i p t i o n s  were e l i g i b l e  f o r  t h e  s t u d y .  

A random sample o f  3 0 0  p a t i e n t s  was c h o s e n ,  and o u t  o f  t h e s e  200 were s e l e c t e d  

f o r  t h e  s t u d y .  T h e r e  were 1 0 0  p a t i e n t s  k e p t  i n  r e s e r v e ,  50 f o r  e a c h  A and B 

g r o u p .  Of t h e  f i r s t  200 p a t i e n t s  i n  U p s a l a  76 had moved, d i e d  or c o u l d  n o t  b e  

f o u n d ,  so 76 p a t i e n t s  from t h e  r e s e r v e s  were added t o  t h e  material. The A g r o u p  

c o m p r i s e d  48 f e m a l e s  and 52 males and t h e  B g r o u p  57 f e m a l e s  and 43 males. The 

a g e  d i s t r i b u t i o n s  o f  t h e  random s a m p l e s  i n  S k e l l e f t e :  and U p s a l a  are shown i n  

F i g u r e  1 .  

PERCENT 

0 
N 

I 

m 
n 

,n 
0 J 

F i g  1 A. The a g e  d i s t r i b u t i o n  o f  
2 0 0  p a t i e n t s  (random s a m p l e )  on 
d i g o x i n  i n  S k e l l e f t e : .  

R E E  
I 
n 

YEBR5 

F i g  1 B. The a g e  d i s t r i b u t i o n  o f  
200 p a t i e n t s  (random s a m p l e )  on 
d i g o x i n  i n  U p s a l a .  

142 



The h e a l t h  d i s t r i c t  o f  S k e l l e f t e d  had 80 0 0 0  i n h a b i t a n t s  i n  1981. T h e r e  were 

66 m e d i c a l  p o s t s ,  36 o f  which were a t t a c h e d  t o  t h e  h o s p i t a l ,  and 30 t o  d i s t r i c t  

m e d i c a l  o f f i c e r s .  During t h e  main p a r t  o f  1978 o n l y  s e v e n  o u t  o f  2 5  posts f o r  

d i s t r i c t  m e d i c a l  o f f i c e r s  were p e r m a n e n t l y  o c c u p i e d .  The r e s t  were a t t e n d e d  t o  

by locums for s h o r t  p e r i o d s .  T h i s  is a common s i t u a t i o n  i n  t h e  n o r t h e r n  p a r t  o f  

Sweden b u t  n o t  i n  C e n t r a l  Sweden. So a comparison w a s  made w i t h  U p s a l a ,  where 

t h e r e  were 594 p h y s i c i a n s ,  459 o f  whom worked a t  t h e  U n i v e r s i t y  Hospital, and 

135 b e i n g  d i s t r i c t  m e d i c a l  o f f i c e r s .  The U p s a l a  area had 1.3 m i l l i o n  i n h a b i -  

t a n t s .  

METHODS 
The p a r t i c i p a n t s  were s e n t  a q u e s t i o n n a i r e  w i t h  n i n e  q u e s t i o n s  a b o u t  e.g. 

t h e  d u r a t i o n  o f  d i g i t a l i s  t r e a t m e n t ,  i t s  d o s a g e  and how t h e  p a t i e n t s  c o m p l i e d  

w i t h  it. The p a t i e n t s  were a l s o  a s k e d  i f  t h e y  knew why t h e y  were t a k i n g  d i g i -  

t a l i s ,  i f  t h e i r  symptoms had improved f o l l o w i n g  t r e a t m e n t  w i t h  d i g i t a l i s ,  and 

i f  t h e y  knew a n y t h i n g  a b o u t  p o s s i b l e  s i d e - e f f e c t s .  T h e r e  were q u e s t i o n s  a b o u t  

t h e  s o u r c e s  o f  t h e i r  i n f o r m a t i o n  on t h e  d r u g  and whether t h e y  c o n s i d e r e d  t h e  

i n f o r m a t i o n  t o  be a d e q u a t e .  The n i n e  q u e s t i o n s  o f  t h e  q u e s t i o n n a i r e  were i d e n -  

t i c a l  f o r  a l l  t h e  p a t i e n t s  b u t  t h e  A and B g r o u p  were g i v e n  d i f f e r e n t  a d d i t i o -  

n a l  i n f o r m a t i o n  t o  f i n d  o u t  i f  t h e  l a n g u a g e  u s e d  i n  t h e  q u e s t i o n n a i r e  c o u l d  

b i a s  t h e  a n s w e r s .  The A g r o u p  w a s  t o l d :  "It i s  i m p o r t a n t  n o t  t o  t a k e  more o f  

t h e  d r u g  t h a n  needed. T h i s  i s  e s p e c i a l l y  t r u e  for L a n a c r i s t ( R ) .  I f  you t a k e  too 

much o f  t h e  d r u g ,  c e r t a i n  u n p l e a s a n t  s i d e - e f f e c t s  may a r i s e " .  The B g r o u p  was 

warned: " I t  is i m p o r t a n t  n o t  t o  t a k e  too l i t t l e  of t h e  d r u g  which i s  needed f o r  

your t r e a t m e n t .  T h i s  i s  e s p e c i a l l y  t r u e  f o r  L a n a c r i s t ( R ) .  You s h o u l d  t a k e  

e x a c t l y  t h e  d o s e  p r e s c r i b e d  and n o t  be careless". The p r e s c r i b e d  d i g o x i n  d o s a g e  

i n  r e l a t i o n  t o  t h e  a g e  o f  t h e  p a t i e n t s  was r e g i s t e r e d .  

P a t i e n t s  i n  b o t h  U p s a l a  and S k e l l e f t e d  who f a i l e d  t o  r e p l y  were r e q u e s t e d  

o n c e  a g a i n  t o  answer t h e  q u e s t i o n s .  

T h e  u s e  of p r e s c r i p t i o n s  f o r  i d e n t i f y i n g  t h e  p a r t i c i p a n t s  w a s  approved by 

S o c i a l s t y r e l s e n s  l a k e m e d e l s a v d e l n i n g  ( N a t i o n a l  Board o f  H e a l t h  and W e l f a r e ,  

Department o f  D r u g s ) .  

RESULTS 

Reply r a t e  

Answers t o  t h e  q u e s t i o n n a i r e s  were r e c e i v e d  from 196 p a t i e n t s  i n  S k e l l e f t e d  

(98 p e r  c e n t )  and from 163 p a t i e n t s  (82 p e r  c e n t )  i n  U p s a l a .  The d i f f e r e n c e  i n  

t h e  r e p l y  r a t e s  i s  s t a t i s t i c a l l y  s i g n i f i c a n t  ( p < O . O O l ) .  I n  S k e l l e f t e 6  and 

U p s a l a  a n s w e r s  were r e c e i v e d  from 97 and 7 7  p a t i e n t s  r e s p e c t i v e l y  i n  g r o u p  A ,  

compared w i t h  9 9  and 86 p a t i e n t s  r e s p e c t i v e l y  i n  g r o u p  B. T h e r e  were n o  s i g n i -  

f i c a n t  d i f f e r e n c e s  i n  t h e  a n s w e r i n g  r a t e s  between t h e  A and B g r o u p  n e i t h e r  i n  

143 



S k e l l e f t e d  (97, 9 9 )  n o r  i n  Upsala ( 7 7 ,  8 6 ) .  I n  S k e l l e f t e d  t h e  e x t r a  i n f o r m a t i o n  

g i v e n  seems t o  h a v e  b i a s e d  t h e  a n s w e r s ,  as t h e  p a t i e n t s  o f  t h e  B g r o u p  who were 

reminded n o t  t o  be c a r e l e s s  i n  t a k i n g  t h e i r  m e d i c i n e ,  r e p o r t e d  a s i g n i f i c a n t l y  

(p. 0.05) h i g h e r  c o m p l i a n c e  t h a n  p a t i e n t s  of t h e  A group. A s i m i l a r  t e n d e n c y  

was found i n  U p s a l a ,  where none i n  t h e  B g r o u p  b u t  f i v e  i n  t h e  A g r o u p  a d m i t t e d  
t h a t  t h e y  had been careless. 

Digoxin d o s a g e  and a g e  

The mean d a i l y  d o s a g e  o f  d i g o x i n  c a l c u l a t e d  from t h e  r e s p e c t i v e  1152 and 619 

p r e s c r i p t i o n s  was 0.193 mg p e r  d a y  i n  S k e l l e f t e d  and 0.212 mg p e r  d a y  i n  U p s a l a .  

T h i s  i n d i c a t e s  t h a t  more p a t i e n t s  t o o k  0.25 mg p e r  d a y  (57 p e r  c e n t  v e r s u s  50 
p e r  c e n t )  i n  U p s a l a  t h a n  i n  S k e l l e f t e i .  The d o s e  f e l l  g r a d u a l l y  w i t h  i n c r e a s i n g  

a g e  i n  b o t h  S k e l l e f t e i  and U p s a l a  ( F i g  2 )  

S k e l l e f t e d  0.291 and U p s a l a  0.243 and a r e  

( p C  0.001). 

* 
D I EUX I N D 

K 
DRILY 

The c o r r e l a t i o n  c o e f f i c i e n t  were i n  

s i g n i f i c a n t l y  d i f f e r e n t  from z e r o  

GUX I N 
RG 
DRILY 

. 3 -  

. 2 -  

F i g  2 A. The r e l a t i o n  between t h e  F i g  2 B. The r e l a t i o n  between t h e  
a g e  and d i g o x i n  d o s a g e  o f  1152 a g e  and d i g o x i n  d o s a g e  o f  619 
p a t i e n t s  i n  S k e l l e f t e 5 .  The corre- p a t i e n t s  i n  Upsala. The corre- 
l a t i o n  c o e f f i c i e n t  r=0.291. l a t i o n  c o e f f i c i e n t  r=0.243. 
(*= The mean d i g o x i n  d o s a g e  f o r  ( * =  The mean d i g o x i n  d o s a g e  f o r  
e a c h  f i v e  y e a r  a g e  i n t e r v a l ) .  e a c h  f i v e  y e a r  a g e  i n t e r v a l ) .  

R e s u l t s  o f  t h e  q u e s t i o n n a i r e s  
( P e r c e n t a g e  o f  196 p a t i e n t s  i n  S k e l l e f t e d  and 163 i n  U p s a l a )  

SKELLEFTEA 
Q u e s t i o n  1 .  

N o  answer 
N o t  q u i t e  s u r e  
More t h a n  5 y e a r s  

2-5 y e a r s  
1-2 y e a r s  

L e s s  t h a n  1 y e a r  

UPSALA 

"HOW l o n g  have you been t a k i n g  L a n a c r i s t ? "  
2 3 
3 4 

39 49 
27 21 
16 6 ( p 4 0 . 0 1 )  
1 1  1 

Have d i s c o n t i n u e d  2 
100 

10 
100 
- 

144 



SKELLEETEA UPSALA 
Q u e s t i o n  2. 

N o  answer 
D o  n o t  know 
0.13 mg 
0.25 mg 

Q u e s t i o n  3. 

N o  answer 
4 t a b l e t  
1 t a b l e t  
1 %  t a b l e t  
2 t a b l e t s  
Another d o s a g e  

One p a t i e n t  who had 
t a k e  1 2  t a b l e t s  p e r  

Q u e s t i o n  4. 

N o  answer 
Every d a y  
S k i p  i t  sometimes 
S k i p  it a l w a y s  
Only on demand 
Have d i s c o n t i n u e d  

Q u e s t i o n  5. 

N o  answer 
N o t  q u i t e  s u r e  
Headache 
I r r e g u l a r  p u l s e  
Insomnia 
Ankle s w e l l i n g  
High b l o o d  l i p i d s  
Body p a i n  

"What i s  t h e  d o s e  p e r  t a b l e t ? "  (it i s  p r i n t e d  o n  t h e  b o t t l e )  

0 
4 

4 6  
50 

100 
- 

7 
2 

34 
5 1  

100 
- 

" H o w  many t a b l e t s  do you t a k e  e a c h  t i m e ? "  

1 
1 

91 
4 
1 
2 

100 
- 

8 
2 

83 
4 
3 
0 

1 0 0  
- 

m i s t a k e n  N i t r o g l y c e r i n  f o r  L a n a c r i s t  s t a t e d  t h a t  h e  c o u l d  
day. 

" H o w  o f t e n  d o  you r e a l l y  t a k e  L a n a c r i s t ? "  

1 
9 1  

5 

6 
85 

2 

1 1 

2 
100 
- 2 

1 0 0  
- 

"For what c o m p l a i n t s  do you t a k e  Lanacr i s t ? "  

4 
18 

3 
1 5  

5 
7 
2 
2 

R e s p i r a t o r y  d i s t r e s s  14 
C h e s t  p a i n  18 
Hyper t e n s i o n  3 
H e a r t  f a i l u r e  53 
O t h e r s  s u c h  as 
h e a r t  e n l a r g e m e n t ,  
a f t e r  m y o c a r d i a l  
i n  f a r  c t  i o n  8 

Some p a t i e n t s  g a v e  s e v e r a l  a n s w e r s .  

9 
1 7  

1 
9 
1 
9 
2 
1 

1 6  
14 

44 
12 ( P ( O . 0 1 )  

6 

I r r e g u l a r  p u l s e ,  a n k l e  s w e l l i n g ,  r e s p i r a t o r y  d i s t r e s s ,  and h e a r t  f a i l u r e  were 
r e g a r d e d  a s  t h e  r i g h t  i n d i c a t i o n s  f o r  d i g o x i n  t r e a t m e n t .  

Q u e s t i o n  6. "Did you improve on L a n a c r i s t ? "  

N o  answer 3 
N o  4 
Y e s  49 
D i f f i c u l t  t o  s a y  44 

1 0 0  

1 0  
3 

38 
49 

1 0 0  
- 

145 



SKELLEETEA UPSALA 
Q u e s t i o n  7 .  "What a r e  t h e  u n p l e a s a n t  s i d e - e f f e c t s  o f  L a n a c r i s t ? "  

N o t  q u i t e  s u r e  
Headache 
Nausea, v o m i t i n g  
D i a r r h o e a  
A n o r e x i a  
E v e r y t h i n g  is 
l o o k i n g  y e l l o w  
T i r e d n e s s  
R e s p i r a t o r y  d i s t r e s s  
I r r e g u l a r  p u l s e  
V e r t i g o  
I n s o m n i a  
Ankle s w e l l i n g  
H e a r t b u r n  
O t h e r  

5 7  
3 
6 
2 
5 

5 3  
4 

1 2  
3 
6 

1 
1 0  
4 
4 
8 
4 
3 
1 
5 

Some p a t i e n t s  g a v e  s e v e r a l  answers. 

Q u e s t i o n  8. "Who or what h a s  t o l d  you what you know a b o u t  L a n a c r i s t ? "  

N o  answer 
Nobody h a s  t o l d  m e  
R e l a t i v e s ,  f r i e n d s  
Newspaper 
R a d i o  or t e l e v i s i o n  
N u r s e  
Doctor 
Pharmacy or o t h e r s  

4 
5 4  

4 
5 
2 
2 

31 
1 

1 2  (P(O.01) 
50 

2 
5 
0 
2 

3 3  
3 

Some p a t i e n t s  g a v e  s e v e r a l  answers. 

Only 37 p e r  c e n t  of t h e  p a t i e n t s  i n  S k e l l e f t e d  who had been i n f o r m e d  by t h e i r  
d o c t o r s ,  were s a t i s f i e d  w i t h  t h e  i n f o r m a t i o n  t h e y  r e c e i v e d .  

Q u e s t i o n  9. "Is t h e  i n f o r m a t i o n  s u f f i c i e n t ? "  

N o  answer 9 
Y e s  1 4  
N o  51 

26 
100 
- D o  n o t  know 

1 5  
1 8  
48 
1 9  

1 0 0  
- 

DISCUSSION 

The u n u s u a l l y  h i g h  r e p l y - r a t e  i n  S k e l l e f t e a  i n d i c a t e d  t h a t  t h e s e  p a t i e n t s  were 

i n t e r e s t e d  i n  t h e  s t u d y .  The s i g n i f i c a n t l y  lower r e p l y - r a t e  i n  U p s a l a  may be 

b e c a u s e  t h e  s t u d y  was r e m o t e l y  c o n t r o l l e d  from t h e  D i s t r i c t  o f  S k e l l e f t e ; .  

Moreover it was easier f o r  t h e  a u t h o r s  t o  r e a c h  t h e  p a t i e n t s  i n  S k e l l e f t e d ,  

where many were known p e r s o n a l l y .  S i g n i f i c a n t l y  (p<O.OOl) more p a t i e n t s  i n  

U p s a l a  were a l s o  t a k e n  from t h e  r e s e r v e s .  Another d i s c r e p a n c y  was t h a t  s i g n i f i -  

c a n t l y  (p<O.O5) more women i n  S k e l l e f t e 6  were randomly c h o s e n  f o r  t h e  s t u d y .  

T h i s  c o u l d  p e r h a p s  i n f l u e n c e  t h e  a n s w e r s  as t h e r e  m i g h t  b e  sex-dependent 

d i f f e r e n c e s  i n  m o r b i d i t y  and m e d i c a t i o n .  Maybe t h e r e  were o t h e r  r e a s o n s  f o r  

t h i s  d i s c r e p a n c y  i n  r e p l y - r a t e ,  s u g g e s t i n g  t h a t  c o n c l u s i o n s  b a s e d  o n  t h e  



d i f f e r e n c e s  between U p s a l a  and S k e l l e f t e a  s h o u l d  be made c a u t i o u s l y .  The r e s u l t s  

of t h e  q u e s t i o n n a i r e  a s  a whole s h o u l d  a l s o  be i n t e r p r e t e d  w i t h  c a u t i o n ,  as t h e  

a n s w e r s  c o u l d  have been i n f l u e n c e d  by t h e  l a n g u a g e  u s e d .  However, t h e  d o s e s  and 

d o s a g e s  o f  d i g o x i n  i s s u e d  a g r e e d  w e l l  w i t h  t h e  r e s u l t s  o f  a n o t h e r  s t u d y  i n  

t h e  D i s t r i c t  of S k e l l e f t e d  ( 5 ) .  I n t e r e s t i n g l y ,  a b o u t  1 5  p e r  c e n t  o f  p a t i e n t s  i n  

S k e l l e f t e a  answered " i r r e g u l a r  p u l s e " ,  which p r o b a b l y  meant a t r i a l  f i b r i l l a -  

t i o n ,  and c o r r e s p o n d e d  f a i r l y  w e l l  t o  t h e  2 0  p e r  c e n t  ECG-verified o c c u r r e n c e  

o f  a t r i a l  f i b r i l l a t i o n  i n  d i g o x i n - t r e a t e d  p a t i e n t s  ( 5 ) .  

The lower d i g o x i n  d o s a g e  i n  t h e  e l d e r l y  when compared w i t h  t h e  younger 

p a t i e n t s  i n  b o t h  S k e l l e f t e d  and U p s a l a  p r o b a b l y  r e f l e c t s  t h e  p h y s i c i a n s '  f e a r  

of c a u s i n g d i g i t a l i s  i n t o x i c a t i o n  i n  t h e  e l d e r l y .  The a g e  o f  t h e  p a t i e n t  i s  s a i d  

t o  b e  o n e  o f  t h e  f a c t o r s  i n f l u e n c i n g  s e n s i t i v i t y  t o  d i g o x i n  ( 7 ) ,  d u e  t o  

d i m i n i s h e d  r e n a l  f u n c t i o n  and l o w  body weight.Moreover, a m a j o r i t y  o f  d i g i t a l i s -  

i n t o x i c a t e d  g e r i a t r i c  p a t i e n t s  i n  S k e l l e f t e a  ( 4 )  had serum d i g o x i n  l e v e l s  w i t h -  

i n  or below t h e  t h e r a p e u t i c  r a n g e ,  s u g g e s t i n g  an a g e  d e p e n d e n t  s e n s i t i v i t y  t o  

d i g i t a l i s .  

One o f  t h e  few s i g n i f i c a n t  d i f f e r e n c e s  i n  t h e  a n s w e r s  between S k e l l e f t e d  and 

U p s a l a  was t h e  l a r g e  number i n  U p s a l a  who t h o u g h t  t h a t  L a n a c r i s t  w a s  g i v e n  f o r  

h y p e r t e n s i o n  ( p < O . O l ) .  The d i f f e r e n c e  i s  d i f f i c u l t  t o  e x p l a i n .  I t  c o u l d  be 

a t t r i b u t e d  t o  c h a n c e  or maybe t h e  f a c t  t h a t  t h e  i n d i c a t i o n  f o r  t r e a t m e n t  was 

more o f t e n  p r i n t e d  on t h e  p r e s c r i p t i o n s  i n  S k e l l e f t e a  t h a n  i n  U p s a l a  ( 7 0  p e r  

c e n t  v e r s u s  4 0  p e r  c e n t ) .  

O t h e r w i s e  t h e  s i m i l a r i t i e s  i n  t h e  a n s w e r s  t o  t h e  q u e s t i o n n a i r e  between Up- 

s a l a  and S k e l l e f t e d  a r e  o b v i o u s .  L a c k  o f  knowledge or m i s u n d e r s t a n d i n g  a s  t o  

why t h e  p a t i e n t s  were t a k i n g  d i g i t a l i s  may have s e v e r a l  c a u s e s .  The i n f o r m a t i o n  

was n o t  p r o v i d e d ,  it was n o t  u n d e r s t o o d ,  it had been f o r g o t t e n ,  t h e  d o c t o r -  

p a t i e n t  c o n t a c t  was t o o  p o o r ,  t h e  d o c t o r s  were changed too o f t e n ,  t h e  p a t i e n t  

was h a r d  o f  h e a r i n g  and s o  on. I t  was q u i t e  o b v i o u s  from q u e s t i o n s  9 and 1 0  

t h a t  many p a t i e n t s  knew l i t t l e  or n o t h i n g  a b o u t  t h e i r  d i s e a s e  or i t s  t r e a t m e n t .  

They also knew l i t t l e  a b o u t  t h e  p o s s i b l e  d i g i t a l i s  s i d e - e f f e c t s .  I n t o x i c a t i o n  

by d i g i t a l i s  r e m a i n s  a major c l i n i c a l  problem. B e l l e r  e t  a 1  ( 2 )  found t h a t  as 

many as 30 p e r  c e n t  o f  t h e  i n - p a t i e n t s  were s u f f e r i n g  from d i g i t a l i s  i n t o x i -  

c a t i o n .  Of 9 1  o u t - p a t i e n t s  i n  S k e l l e f t e a ,  5 p e r  c e n t  were found t o  be c e r t a i n l y  

i n t o x i c a t e d  and 2 p e r  c e n t  p o s s i b l y  so ( 5 ) .  I n  S k e l l e f t e d  a b o u t  5 p e r  c e n t  knew 

a b o u t  t h e  a d v e r s e  e f f e c t s  o f  d i g i t a l i s ,  b u t  on t h e  o t h e r  hand j u s t  as many 

l i s t e d  symptoms t h a t  c o u l d  n o t  be a s c r i b e d  t o  it. If p a t i e n t s  e r r o n e o u s l y  

a t t r i b u t e  a d v e r s e  r e a c t i o n s  t o  t r e a t m e n t  by d i g i t a l i s  t h e y  m i g h t  d i s c o n t i n u e  

t h e  d i g i t a l i s  t h e r a p y .  The o c c u r r e n c e  o f  i n t o x i c a t i o n  by d i g i t a l i s  c o u l d  be 

r e d u c e d  i f  p a t i e n t s  knew more a b o u t  i t s  s i d e - e f f e c t s .  They m i g h t  t h e n  e a r l i e r  

r e c o g n i s e  t h e  s i g n s  o f  i n t o x i c a t i o n  and so r e p o r t  e a r l i e r  to t h e i r  d o c t o r s .  

Many p a t i e n t s  found it d i f f i c u l t  t o  s t a t e  i f  t h e y  had been improved by d i g i -  

147 



t a l i s  t r e a t m e n t .  T h i s  m i g h t  have been b e c a u s e  t h e  t r e a t m e n t  and/or t h e  d i a g n o s -  

is were wrong or d i u r e t i c  t r e a t m e n t  had made it d i f f i c u l t  t o  a s s e s s  t h e  

e f f i c a c y  o f  d i g i t a l i s .  T h i s  a g r e e s  w i t h  t h e  r e s u l t s  o f  o t h e r  s t u d i e s  showing 

t h a t  many g e r i a t r i c  p a t i e n t s  a r e  d i g i t a l i z e d  u n n e c e s s a r i l y  ( 3 ) .  

From t h i s  s t u d y  it i s  o b v i o u s  t h a t  t h e  i n f o r m a t i o n  g i v e n  t o  or u n d e r s t o o d  

by p a t i e n t s  i s  i n s u f f i c i e n t .  I t  was n o t  known how many p a t i e n t s  were c o r r e c t l y  

i n f o r m e d ,  b u t  f o r g o t  or m i s u n d e r s t o o d  t h e  i n f o r m a t i o n  g i v e n .  I t  i s  i m p o r t a n t  

t o  m a k e  s u r e  t h a t  t h e  p a t i e n t  h a s  u n d e r s t o o d  t h e  i n f o r m a t i o n  and t o  r e p e a t  it, 

i n  o r d e r  t o  a c h i e v e  e f f e c t i v e  m e d i c a t i o n  w i t h  d i g i t a l i s .  One o f  t h e  most common 

r e a s o n s  f o r  a breakdown i n  p a t i e n t - d o c t o r  communication i s  p r o b a b l y  f r e q u e n t  

c h a n g e s  o f  d o c t o r s .  The p a t i e n t s  were g e n e r a l l y  informed by t h e i r  d o c t o r s  which 

i s  b o t h  n a t u r a l  and d e s i r a b l e .  A d d i t i o n a l  i n f o r m a t i o n  and e x p l a n a t i o n  c o u l d  b e  

g i v e n  by n u r s e s  t o  b o t h  o u t - p a t i e n t s  and i n - p a t i e n t s .  P h a r m a c i s t s  may s u p p l e -  

ment t h i s  i n f o r m a t i o n  t h r o u g h  p r a c t i c a l  a d v i c e  a b o u t  t h e  s t o r a g e  o f  t h e  d r u g ,  

i t s  s t a b i l i t y ,  t h e  i m p o r t a n c e  o f  t a k i n g  t h e  correct d o s e s  a t  t h e  correct t i m e  

and how t o  t a k e  it i n  r e l a t i o n  t o  food. 

A n e c e s s a r y  c o n d i t i o n  f o r  a w e l l - f u n c t i o n i n g  p a t i e n t  i n f o r m a t i o n  s y s t e m  is 

t h a t  t h e  p a t i e n t  a l w a y s  meets t h e  same d o c t o r  f o r  c o n s u l t a t i o n .  Another p r e -  

r e q u i s i t e  f o r  good communication i s  t h a t  t h e  d o c t o r  u s e s  a l a n g u a g e  t h a t  t h e  

p a t i e n t  c a n  u n d e r s t a n d .  Maybe o t h e r  c h a n g e s  i n  t h e  m e d i c a l  c a r e  a r e  n e c e s s a r y .  

Good c o n t i n u i t y  i s  also i m p o r t a n t  when j u d g i n g  t h e  e f f i c a c y  o f  t h e  d i g i t a l i s  

t r e a t m e n t ,  when a d e c i s i o n  i s  made t o  d i s c o n t i n u e  or c o n t i n u e  a g i v e n  t r e a t -  

ment. I n  t h i s  way u n n e c e s s a r y  d i g i t a l i s  m e d i c a t i o n  may b e  a v o i d e d .  

Guided by t h e  r e s u l t s  o f  t h e  p r e s e n t  s t u d i e s  w e  hope t h a t  t h e  f o l l o w i n g  

s t e p s  w i l l  assist i n  improving t h e  p a t i e n t s  knowledge o f  t h e i r  m e d i c a t i o n .  

When d i g o x i n  t r e a t m e n t  is s t a r t e d :  

T e l l  t h e  p a t i e n t  t h e  name o f  t h e  c a r d i a c  g l u c o s i d e  b e i n g  u s e d  and why t r e a t -  
ment h a s  t o  be s t a r t e d .  

T e l l  t h e  p a t i e n t  what symptoms w i l l  p r o b a b l y  b e  r e l i e v e d  by t h e  t r e a t m e n t .  

S t a t e  t h e  d o s a g e ,  t h e  l e n g t h  o f  t r e a t m e n t  and t h e  i m p o r t a n c e  of t a k i n g  t h e  
d o s e s  e x a c t l y  a s  p r e s c r i b e d .  

Make t h e  p a t i e n t  aware o f  t h e  a d v e r s e  e f f e c t s  which n e c e s s i t a t e s  a new 
c o n s u l t a t i o n  w i t h  t h e  d o c t o r .  

Give a l l  t h i s  i n f o r m a t i o n  t o  t h e  p a t i e n t  i n  w r i t i n g  as w e l l  a s  v e r b a l l y .  

Write on t h e  p r e s c r i p t i o n  t h e  symptom(s) which t h e  d r u g  w i l l  r e l i e v e  or c u r e .  

Record t h e  i n d i c a t i o n  f o r  t h e  t r e a t m e n t .  

A t  t h e  n e x t  v i s i t :  

A s k  f o r  d e t a i l s  o f  any improvement i n  h e a r t  symptoms and a s k  f o r  any a d v e r s e  
e f f e c t s  . 
A t  e a c h  v i s i t  r e c o n s i d e r  i f  t h e  d o s a g e  s h o u l d  be changed or d i g i t a l i s  s h o u l d  
b e  withdrawn. 

A s k  t h e  p a t i e n t  i f  h e / s h e  u n d e r s t o o d  t h e  i n f o r m a t i o n  and s u p p l e m e n t  it i f  
n e c e s s a r y .  

148 



- Emphasize the importance of taking the medicine in the doses and at the 
intervals exactly as prescribed. 

Many of these suggestions are familiar and obvious and are already followed 

widely. However, it appears to be very difficult to get information across to 

patients. If these proposals are followed, we hope that digitalis intoxications 

and unnecessary digitalis prescribing will decrease and that improved coope- 

ration by patients will be achieved, particularly among those who need digi- 

talis therapy. 

ACKNOWLEDGEMENTS 

We would like to thank the National Corporation of Swedish Pharmacies, 
pharmacist Gunnar Eriksson at the pharmacy (Kronan) in Upsala, and ASS. 
prof. Goran Sundlof , Department of Internal Medicine, Akademiska sjuk- 
huset, Upsala, for valuable cooperations. 

R E F E R E N C E S  

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

Ander, S .  & Tibblin, S.: Manniskors medicinska kunskaper. Soc Med Tidskr 
hafte 1 9 7 4 ;  1 0 :  6 5 4  - 660. 
Beller, G.A., Smith, T.W., Abelman, W.H., Haker, E. & Hood, W.B.: 
Digitalis intoxication. A prospective clinical study with serum level 
correlations. N Engl J Med. 1 9 7 1 ;  284: 9 8 9  - 997. 
Boman, K., Allgulander, S. & Skoglund, M.: Is maintenance digoxin 
necessary in geriatric patients? Acta Med Scand 1 9 8 1 ;  210: 4 9 3  - 495. 
Boman, K.: Digitalis intoxication in geriatric in-patients. Acta Med 
Scand. Accepted for publication. 

Boman, K. & Mollerberg, H.: Digoxinintoxikation i ett oselekterat 
patientmaterial. Lakartidningen 1 9 7 9 ;  76: 4 1 0 8  - 4 1 1 0 .  
Bottiger, L.E.: Kan patienten ratt skota sin medicinering? Nord Med 
1969; 82: 1 6 0 5  - 1606. 
Ewy, G.A., Kapadia, G.G., Yao, L., Lullin, M. & Marcus, F.I.: Digoxin 
metabolism in the elderly. Circulation 1 9 6 9 ;  3 9 :  4 4 9  - 453. 
Hellstrom, K. & Leijd, B.: Vad vet patienter om sina sjukdomar och 
deras medikamentella behandling? Lakartidningen 1 9 7 6 ;  7 3 :  9 6 8  - 9 7 0 .  
Johnston, G.D. & Mc Devitt, D.G.: Digoxin compliance in patients 
from general practice. Brit J Clin Pharmacol 1 9 7 8 ;  3 3 9  - 343. 
Johnston, G.D., Kelly, J.G. & Mc Devitt, D.G.: Do patients take 
digoxin? Br Heart J 1 9 7 8 ;  40: 1 - 7. 

Adress for reprints: 

Kurt Boman, M.D. 
Department of Internal Medicine 
Skelleftez hospital 
931 86 SKELLEFTEW 
Sweden 

149