Dementia in developing countries: Does education play the same role in India as in the West?

Evidence suggests that education protects from dementia by enhancing cognitive reserve. However, this may be influenced by several socio-demographic factors. Rising numbers of dementia in India, high levels of illiteracy and heterogeneity in socio-demographic factors provide an opportunity to explore this relationship. Objective To study the association between education and age at dementia onset, in relation to socio-demographic factors. Methods Association between age at dementia onset and literacy was studied in relationship to potential confounding factors such as gender, bilingualism, place of dwelling, occupation, vascular risk factors, stroke, family history of dementia and dementia subtypes. Results Case records of 648 dementia patients diagnosed in a specialist clinic in a University hospital in Hyderabad, India were examined. All patients were prospectively enrolled as part of an ongoing longitudinal project that aims to evaluate dementia subjects with detailed clinical, etiological, imaging, and follow-up studies. Of the 648 patients, 98 (15.1%) were illiterate. More than half of illiterate skilled workers were engaged in crafts and skilled agriculture unlike literates who were in trade or clerical jobs. Mean age at onset in illiterates was 60.1 years and in literates 64.5 years (p=0.0002). Factors independently associated with age at dementia onset were bilingualism, rural dwelling and stroke, but not education. Conclusion Our study demonstrates that in India, rural dwelling, bilingualism, stroke and occupation modify the relationship between education and dementia.