Abstract
The Global Burden of Disease Study (1997) reported 9·4 million deaths in India, of which 619 000 were from Stroke, and the Disability Adjusted Life Years that were lost almost amounted to 28·5 million: nearly six times higher than that due to Malaria (1). As life expectancy increases, India will face enormous socioeconomic burden to meet the costs of management of chronic diseases such as stroke (2). However, there is paucity of standardized and comparable population-based data on incidence and on stroke epidemiology (3). For this purpose, WHO has proposed the use of STEPS Stroke instrument (2, 4). The present report describes data collection, management and results on patients having first-ever stroke (FES) in a prospective population-based study.
Between January 2005 and December 2006, a well-defined community (H-ward) with verifiable census data, and representative of population structure of Mumbai was selected. Of 337 391 permanent residents, 156 861 people age over 25 years who were eligible for survey were screened for FES. The uniform terminologies as per WHO STEPwise approach to stroke surveillance (Version: 2) was the operational protocol (5).
The area hospitals, nursing homes, CT diagnostic centres, and around 120 local medical practitioners agreed to cooperate in the study and by weekly personal visits the medical research officers remained in constant touch with them. However, confirmation of stroke diagnosis required its scrutiny by a medical physician or neurologist and was supported by diagnostic test (e.g. CT scan). There were no false-negative cases. All potential stroke (FES) patients as identified were followed up (28 days) by medical research officers either by using ‘hot pursuit’ (prospective case registration) or by ‘cold pursuit’ (retrospective case registration) or a combination of both. Multiple overlapping sources of information were used for completeness of case ascertainment. In case of fatal events, death certificates, as issued by qualified medical practitioners, were scrutinized at the municipal death record office and where possible ‘verbal autopsy’ was carried out to ascertain the primary cause of death.
Five hundred and twenty-one new cases of stroke (cerebrovascular disease) were identified; of which 456 (238 males and 218 females) had FES indicating an annual incidence of 145 per 100 000 people (95% CI 120–170); age standardised rate [to 1996 world population by direct method of Segi (6)]: 152 FES per 100 000 people per year (95% CI 132–172). Mean age was 66 years (SD 13·60), women [mean age 68·9 years (13·12)] were older than men [63·4 years (13·53)]. CVD diagnosis was supported by CT in 407 (89%) of 456 FES cases. Three hundred and sixty-six (80·2%) had ischaemic CVD, 81 (17·7%) had haemorrhagic CVD, and nine (1·9%) were of unspecified category. Hypertension (blood pressure > 140/90 mmHg) alone or in various combinations was present in 378 (82·8%) cases. By 28 days, 136 (29·8%) of 456 patients with FES died; 82 (17·9%) were stroke deaths, whereas 54 (11·8%) deaths were related to comorbid disorders. Of 320 survivors, 38·5% had moderate to severe disability (modified Rankin score 3–5).
The results of Mumbai stroke registry are nearly similar to those reported from industrialized cities like Perth (Australia), Erlangen (Germany), and South London (UK) (7). Similar studies from other regions of India will help in planning intervention and prevention strategies. On account of scarce resources, modern stroke care (intensive units, neuroimaging, thrombolytics, etc.) for evaluation and management is beyond the reach of majority of patients in developing nations (8). Nonetheless risk factors for stroke are mainly conventional (9) and intervention to reduce raised blood pressure, campaign against tobacco use, lifestyle changes to reduce salt intake and consumption of saturated fats, and promotion of physical activity will prove beneficial. Health education and National Health Policy in support of above goals are recommended.