I have a plan to do thesis for my public health master's degree on dementia among elderly people in South India. Please suggest a topic which is of public health importance.
The WHO SAGE India study would have affective and cognitive health measures that would contribute to your thesis. The variables collected include depression, a battery of cognitive tests impacted early in the dementing process, a timed walk, grip strength, vision, caregiving, health care utilization, social networks and other measures that would be very important predictors/determinants/outcomes of dementia. See for instance: http://apps.who.int/healthinfo/systems/surveydata/index.php/catalog/65 or www.who.int/healthinfo/sage and colleagues at the International Institute for Population Science in Mumbai.
An interesting and needed topic for more research is elder abuse. Since you asked specifically about dementia, you could look at caregiver abuse or abuse by the patient to the caregiver or if in a long term care facilty, abuse of other residents.