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CEREBROVASCULAR ACCIDENTS (STROKES) IN DIFFERENT AGE GROUPS

SV Joshi*, HL Dhar**

*Technical Officer; **Director, Medical Research Centre, Bombay Hospital, 12 Marine Lines, Mumbai 400 020.

Strokes constitute 9.37% of total neurological cases and maximum strokes are cerebral. The incidence increased with age. Left infarct was predominent (62.5%) in young compared to elderly (50.5%) while right infarct is more in elderly (45.4%) than young (37.5%). Multiinfarct (4.13%) occurs only in elderly. Low serum cholesterol (23.5%) and low haemoglobin (20%) values were observed in strokes. Both hypertension 61.0% and diabetes 35.24% are risk factors contributing to high mortality in elderly.

INTRODUCTION

Incidence of cerebrovascular accidents (stroke) is known to increase with age mainly due to atherosclerosis.[1] However, a significant proportion of strokes occur in adolescents and young adults.[2] According to a study from Bangalore, percentage of young patients involved was as high as 20-30%.[3]

Present study is an analysis of data comparing the incidence of stroke in young, middle aged and elderly in relation to risk factors involved including biochemical findings.

PATIENTS AND MATERIAL

105 patients (20-94 years) of stroke admitted to Medical Research Centre, Bombay Hospital during the year 1996 (Jan-Dec) were included in this study. The incidence was analysed as per age group < 40, 40-59, 60 and above. The risk factors, such as hypertension, diabetes and altered lactic dehydrogenase (LDH), serum glutamate oxalate transaminase (SGOT), serum glutamic pyruvate transaminase (SGPT), serum lipids, high density lipoprotein (HDL), low density lipoprotein (LDL) were included. Effect of various drugs e.g. antihypertensives, antiplatelet agents and anticoagulants in delaying mortality was also studied.

RESULTS

Results show that cerebrovascular accidents increase with age both in males and females upto 69 years (Table 1). Cerebral strokes were maximum (41.91%) followed by ischaemic (21.9%), brain stem infarct (12.38%), embolic phenomenon (10.48%), multi-infarct (9.52%) and thrombolytic episode (3.81%). Incidence of different types of stroke with age has been shown in graph 1. Among young (< 40) left infarct was predominant (62.5%) compared to right infarct (37.5%). In higher age group (> 40 years) incidence of left and right infarct were comparable 50.51% and 45.36% respectively however, 4.13% had multiinfarct. In the elderly, risk of stroke increases with hypertension (60.95%), diabetes (35.24%) and ischaemic heart disease (IHD) 24.76%. Below the age of 40 years, out of 8, only one patient suffered from diabetes and another from hypertension. In the middle age group (40-59 years) out of 34 patients 15 were diabetic and 20 hypertensive whereas in the above 60 group, out of 63, 43 patients were hypertensive and 21 diabetic.

Following biochemical values were raised : cholesterol (21.9%), LDH (25.71%), SGOT (13.35%), SGPT (11.4%), total lipids (7.62%), LDL (5.7%) however, haemoglobin was low in 20% of patients, cholesterol was low in 23.5%.

TABLE 1
Agewise incidence of cerebrovascular accidents
Age 20-29 30-39 40-49 50-59 60-69 70-79 80+
Males 3 2 7 19 21 14 5
Females 2 1 2 6 13 7 3
Total(n) 5 3 9 25 34 21 8
% 4.8 2.9 8.6 23.8 32.4 20.0 7.6


Fig. 1
Fig 1 :

However, presence of albumin in urine and haematuria was found in 19% and 16.2% respectively.

Following clinical symptoms were present : speech defect in 55.24%, difficulty in swallowing 4.76% and diminished vision in 1.90% of cases. Speech was affected mostly in elderly subjects (55.55%) and middle aged (56%) followed by adult (37.5%). 50% of patients who suffered from CVA received antiplatelet agents. (e.g. aspirin) of which 41.27% were elderly, 80% belonged to middle age group but none among the adults however, 12.5% of adults, 23.53% of middle aged and 15.8% of elderly were prescribed anticoagulants. Vasodilators were used in 12.5% adults, 17.65% middle aged and 36.5% in elderly group. The elderly subjects mostly received antihypertensive drugs (73%) compared to adults (12.5%) and middle aged (5.88%). However, mortality increased with age (12.5%) (< 40 years) 14.0% (40-59 years) and 25.39% in 60 group.

DISCUSSION

Among ten per cent of cerebrovascular accidents, cerebral strokes were maximum (41%) followed by ischaemic changes and brain stem infarct. Hypertension and diabetes are the main risk factors and mortality was maximum in elderly. Occurrence of stroke in the present series is comparable with figures quoted in neurological registry (6.5 - 7.8%)[5] but the incidence is less than half of those reported by Dalal et al (20%) from Bombay[4] which could be due to improved facilities. In our series, the incidence of strokes is low (7.62%) in young (< 40 years) compared to those reported from Rohtak.[6] In middle aged (30%) and elderly (64%), cerebral strokes were more frequent compared to young (7%). Increased incidence in higher age group[7] is likely to be due to atherosclerosis and hypertension (61%) as well as diabetes 35.24%. Ischaemic stroke in young (< 40) constituted 8.7% compared to Western data as high as 71%.[8] It might be due to less incidence of rheumatic heart disease and nonatherosclerotic cause of ischaemia leading to cardiogenic embolism[1] and timely intervention.

Prevalence of hypertension (60.95%) in advanced age group is the commonest risk factor for all types of strokes[9] followed by diabetes mellitus (35.24%).[10],[11] Low serum cholesterol values were correlated in 23.5% cases of strokes as reported by Masamitsu.[12] We also found relationship with raised HDL (5.71%). Similar findings have been reported by others.[10],[13]

Low haemoglobin levels (20%) in upper age groups (40 to 60+) could be contributory to cerebral ischaemia[14] however, antihypertensive (61%)and anticoagulant therapy (21.9%) could be a protective factor in ischaemic strokes.[15],[16]

Nearly twofold mortality (21.65%) in upper age groups (middle aged and elderly) compared to young (12.51%) may attribute to atherosclerosis and hypertension.[15]


REFERENCES

1.Curb JD, Abbot RD, Maclean CJ, Rodriquez BL, Burchfiel CM, Sharp DS, Ross W, Yano K. Age related changes in stroke risk in men with hypertension and normal blood pressure. Stroke 1996; 27 (5) : 819-24.

2.Khadilkar SV. (Editorial) Strokes in adolescents and young adults. JAPI 1997; 45 (4) : 261-62.

3.Nagaraja D, Taly AB. Strokes in young. Progress in clinical neurosciences. 1988; 2 : 129-45.

4.Dalal PM, Dalal KP. Strokes (CVD) in young and elderly. Incidence, risk factors and prevention. In : Medicine update (APICON 92) ed. S. Mukherjee. 1992; 2 Chap.

5.Gururaj G, Satishchandra P, Subbakrishna DK. Epidemiological correlates of stroke mortality observations from a tertiary institution. Neurology India 1995; 43 : 29-34.

6.Bansal BC, Dhamija RK, Mittal S. An epidemiological study of cerebrovascular disease in urban and rural areas of Rohtak India. Proceedings of International symposium on Neuroepidemiology Bombay. 1991.

7.Louis W, Niessen Jan J, Barendregt Luc Bonnex, Koudstaal PJ. Stroke trends in an aging population. Stroke 1993; 24 (7) : 931-39.

8.Naomi RS, Revital RA, Tamir A, Gera H, Eldar R. Stroke in the young the Israel incidence and outcomes. Strokes 1996; 27 (5) : 838-41.

9.Jaakko T, Daiva R, Juhani S, Sarti C, et al. Ten year trends in stroke incidence and mortality in the FINMONICA study. Stroke 1996; 27 (5) : 825-32.

10.Dalal PM, Dalal KP, Rao SV, Parikh BR. Strokes in West Central India : A prospective case control of "Risk factors" In; Neurology in Europe. eds. D. Bartko et al, London, John Libbey and Co. Ltd. 1989; 16-20.

11.Abbot RS, Donahue RP, MacMohan SW, Reed DM, Yano K. Diabetes and the risk of stroke. The Honolulu heart program. JAMA 1987; 257 : 949-52.

12.Masamitsu Konishi, Hiroyasu So, Yoshio Komachi, Minorulida Takashi, Shimamoto, David R, Jacobs Ausushi Terao, Shunroku Baba Tomoka, et al. Association of serum total cholesterol. Different types of strokes and stenosis distribution of cerebral arteries. The Akkita Pathology study. Stroke 1993; 24 (7) : 954-64.

13.Kar AM, Garg RK, Gaur SPS. Serum lipids and stroke. Neurology India 1993; 41 : 1-6.

14.Kiyohara Y, Fujishima M, Ishitsuka T, et al. Effects of hematocrit in brain metabolism in experimentally induced cerebral ischaemia in spontaneously hypertensive rats (SHR). Stroke 1985; 16 : 835-40.

15.Svend S, Stig H. Why does antihypertensive treatment prevent stroke but not myocardial infarction. The Lancet 1987; 19 : 658-60.

16.Boysen G. Anticoagulant and antiplatelet therapy in cardioembolic stroke. Cerebrovascular Dis 1994; 4 (suppl.) : 29-33.



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