Lower Perceived Socioeconomic Status Increases Odds of Parkinson's Disease

The association between socioeconomic status (SES) and Parkinson's disease (PD) has been investigated in few studies till now. A recent study form Tehran demonstrated that lower wealth index, a lower perceived SES and academic education are associated with increased the odds of PD.

The most prevalent neurodegenerative movement disorder, Parkinson’s disease (PD), is caused by the selective loss of dopamine-producing cells and the inappropriate accumulation of alpha-synuclein in Lewy bodies in the brain and spinal cord. The symptoms of tremors, muscle stiffness, bradykinesia/akinesia and posture instability are caused due to reduced dopamine levels in the basal ganglia. In industrialised countries, 0.3% of the general population and 1%–3% of people over 60 are affected by PD.

Numerous studies over years have revealed that PD is influenced by both genetic and environmental factors. A family history of PD, a history of head trauma, exposure to insecticides, anxiety or depression, and consuming dairy products have all shown a direct association with PD. In contrast, many studies have found an inverse association between physical activity, smoking, coffee and alcohol consumption with PD. Moreover, demographic characteristics, such as age, gender, ethnicity and socioeconomic status (SES), may be associated with PD. Age is the most significant known risk factor for PD; so PD has emerged as a serious public health concern in older societies. This concern is more severe in low/middle-income countries due to a lack of preparation to face the high burden of chronic diseases such as PD.

One of the factors related to various diseases is SES. SES is important since it has been known to affect the occurrence of certain diseases by affecting various environmental and social factors.Although the association between SES and certain chronic diseases has been studied,a few studies have investigated the association between SES and PD, and these studies have shown conflicting results.

Najafi et al conducted a case–control study based on incident cases in Tehran. Several variables were used to measure SES. Their potential association with PD was determined after adjusting the confounding variables. The study’s findings revealed that based on the wealth index, the intermediate people had a lower chance of developing PD than the deprived. This association was seen in both sexes. However, affluent women had a lower chance of getting PD than the deprived women. Also, the odds of PD among individuals with intermediate and affluent perceived SES were lower than those of the deprived. In the analysis by sex, this association was confirmed in all categories for both men and women. Overall, the results of our study showed that people of the higher SES category, whether based on the wealth index or the perceived status, had a lower chance of developing PD.

In their study, a significant inverse association was found between perceived SES and PD. When compared with women, the magnitude of the association was slightly stronger in men. When compared with individuals from the intermediate and affluent perceived SES categories, the higher chance of developing PD among the deprived can be biologically justified. The lack of dopamine in the brain has a direct effect on the development of Parkinson’s disease. On the other hand, due to this decrease in dopamine, positive feelings such as satisfaction or pleasure also decrease, so one’s perception of SES may be generally lower. A person’s perceived SES reveals a sense of social class identity, which can be influenced by his or her past, present status and prospects for the future

The study indicated that, based on the wealth index, both men and women from the intermediate category had lower odds of developing PD when compared with those from the deprived category. Moreover, when compared with academic education, illiteracy and/or a primary level of education decreased the odds of PD. Individuals who had the lowest perceived SES had higher odds of PD compared with all other categories among the Iranian population.

Reference

Fereshteh Najafi, Mohammad Ali Mansournia, Ibrahim Abdollahpour, Mohammad Rohani, Farhad Vahidand Saharnaz Nedjat Association between socioeconomic status and Parkinson’s disease: findings from a large incident case–control study BMJ Neurology Open http://dx.doi.org/10.1136/bmjno-2022-000386