Postcode a stroke predictor

PEOPLE who live in poorer areas have more strokes and have them at a younger age than those in wealthier areas, according to new research in the MJA.

And another paper in the same issue of the MJA shows that one in 10 people cannot identify any of the warning signs of stroke.

The first paper showed the annual age-standardised stroke rate was 70% higher among patients in the most deprived areas compared with those from the least deprived areas (131 per 100 000 person-years v 77 per 100 000 person-years). (1)

“This may be explained by a higher prevalence of risk factors among these populations”, the researchers wrote.

The research was based on analysed data on 3077 stroke patients from three population-based studies in Perth, Melbourne and Auckland between 1995 and 2003. The study included analysis of socioeconomic deprivation in the patients’ postcode or meshblock (a New Zealand area unit of about 90 people).

Compared with stroke sufferers in the wealthier areas those in the poorer areas tended to be younger (68 years vs 77 years), had more comorbidities such as hypertension and diabetes, and were much more likely to smoke. After adjusting for age, the study found that 19% of strokes were attributable to living in the most deprived areas compared with the better-off areas.

However, there was no clear relationship between socioeconomic status and survival 12 months after a stroke, which suggested that health care systems were not discriminating against people in disadvantaged areas, the researchers wrote.

Professor Craig Anderson, senior director of the George Institute for Global Health and a coauthor of the paper, said the paper emphasised the need for “lifestyle management” at a family or community level to prevent risk factors.

However, Professor Anderson acknowledged that lifestyle modification was challenging as it was influenced by everything from employment and education levels to the accessibility of bike paths.

In a related editorial, MJA editor Dr Annette Katelaris agreed that the effect of socioeconomic status on health was multifactoral. (2)

Professor Anderson said there was also a role for individual doctors to reduce risk factors by ensuring that patients had well controlled blood pressure, and by encouraging improved diet, exercise and smoking habits.

“People from more deprived areas need more targeted health advice and treatment by the very nature of where they live and how they behave”, he said.

Professor Anderson said that doctors in these areas also have a responsibility to ensure that patients are aware of stroke risk factors and warning signs.

Public awareness of stroke risk factors and warning signs is very limited, according to the second paper in the latest MJA. (3)

The survey of 251 people found that slurred speech was the most recognised stroke warning sign (identified by 61%), followed by dizziness (42%) and numbness (42%).

“Notably one in 10 could not identify any warning signs even when presented with a list of them”, the researchers wrote.

Hypertension was identified by 71% of the survey respondents as a stroke risk factor, followed by smoking (53%), while all other risk factors such as obesity and family history of stroke were identified by less than half the sample.

The research also found that a public education campaign during National Stroke Week had no significant effect on awareness of stroke symptoms.

– Sophie McNamara

1. MJA 2011; 194: 10-14
2. MJA 2011; 194: 3
3. MJA 2011; 194: 16-19

Posted 4 July 2011