Parkinson’s disease (PD) is found more frequently in men than in women, occurring in men 50% more than in women. In addition to the differences in incidence, there are some other differences seen in PD in men versus women.1,2
Why is Parkinson’s disease more common in men than women?
Researchers aren’t yet sure why there is a difference in the rate of PD between men and women. Some suggested explanations are the protective effect of estrogen in women, the higher rate of minor head trauma and exposure to occupational toxins in men, and genetic susceptibility genes on the sex chromosomes.1
Onset, progression, and mortality of Parkinson’s disease in men
Women on average develop the disease 2.1 years later than men. However, other studies have found no differences between men and women for the age of onset.3 One study that followed PD patients for 6 years found that despite the increased rate of PD in men, men and women acquired the disease at the same age and have the same progression and duration of disease. The study also found that men and women patients with PD have the same average life expectancy, which is different than in the general population without PD, in which women have a longer life expectancy than men.5 Symptoms of PD also tend to progress more rapidly in men. However, larger scale, placebo controlled studies are required for more conclusive evidence on the differences between women and men in the symptoms and treatment of PD.
Symptoms of Parkinson’s disease in men
In general, men with PD have similar motor and non-motor symptoms as women with PD. However, men have more difficulties with REM sleep behavior disorder (acting out physically while dreaming). Women report more symptoms of tremor while men report more symptoms of rigidity. Other symptoms of PD include:
- Tremor of the hands, arms, legs, or face
- Rigidity of the limbs and trunk
- Slowness of movement
- Gradual loss of spontaneous movement (bradykinesia)
- Impaired balance
- Lack of coordination
- Sleep disturbances
- Impaired memory or thinking
- Difficulties with urination or constipation6
Although PD is highly individual, and symptoms vary in their presence and severity between patients, there may be some differences in how these symptoms appear in men compared to women with PD. Women more often experienced tremor (67%) than men (48%).4 Women have better scores for motor abilities than men, based on the scoring of the Unified Parkinson’s Disease Rating Scale. These differences in motor symptoms were significant only in patients who had PD for more than 5 years.3 Women report more symptoms of depression and reduced quality of life with PD.
Treatment of Parkinson’s disease in men
Levodopa, the standard medication to treat PD, is metabolized differently in men compared to women, so the dosage for men with PD is higher than for women. The difference in dosage for men is perhaps explained by their generally larger body mass. Men also have fewer side effects with levodopa, known as levodopa-induced dyskinesia (involuntary movements).5,7