Table 1.

Summary of Previous Studies on Suicide in PD

Author	Year of publication	Country	Title	Population	Result
Stenager EN, et al. 4	1994	Denmark	Suicide in patients with Parkinson's disease‐ An epidemiological study	458 PD patients followed‐up over mean period of 5.7 years (0 to 17 years), 254 deaths with 2 suicides. Local catchment population used as reference 435,000; suicide rate = 30/100,000.	The number of expected suicide was 1.06 for men and 0.55 for women. The expected and observed suicide rates were not statistically significant for either gender.
Myslobodsky M, et al.5	2001	USA	Are patients with Parkinson's disease suicidal?	Total number of deaths was 12,430,473 from 1991 to 1996. Of these, 99,109 committed suicide, 144,364 of deaths were Parkinson patients of 40 years old and above. of these, 122 committed suicide	Only 0.08% (122) persons with PD died by suicide, as compared with 0.8% (99,109) in the reference population. People who committed suicide were younger than people who died from other causes (72.2 vs 81.2 years for patients with PD, t = 13.3, P < .001; 59.6 vs 74.9 years for the referent population, t = 335.9, P < .0001). PD suicide deaths were significantly older than suicide deaths in the reference population (72.2 vs 59.6 years, t = 9.7, P < .001). The rate of suicide among married patients with PD was higher than among single patients with PD.
Mainio A et al.6	2009	Finland	Parkinson's disease and suicide: a profile of suicide victims with Parkinson's disease in a population‐based study during the years 1988–2002 in Northern Finland	546 suicide victims aged 50 and above without PD vs 9 Suicide victims with PD	Suicide occurred in 1.6% of hospital‐treated Parkinson's disease patients, indicating a rather low prevalence of suicide in this group of patients. The profile of PD persons who completed suicide was as follows: male subject with recently diagnosed disease, living in rural area, having multiple physical illnesses, and having attempted suicide before.
Kostić et al.7	2010	Serbia	Suicide and suicidal ideation in Parkinson's disease	Suicide as outcome in PD patients 102 PD patients, followed up for 8 years, 2 patients committed suicide	The suicide‐specific mortality was 5.3 (95% CI 2.1–12.7) times higher than expected. Both patient who committed suicide had major depression
Lee T et al.8	2016	Korea	Increased Suicide risk and clinical correlates of suicide among patients with Parkinson disease	4362 Parkinson patients (from 1996 to 2012) 29 PD suicides matched with 116 non‐suicide controls	Standardised Mortality ratio for PD patients was 1.99 (95% CI 1.33 to 2.85) which was 2 times higher than the general population. Risk factors: male gender; upper extremity or generalised onset of motor symptoms; history of depressive disorder, delusion or any psychiatric disorder; and higher L‐dopa dosage.