Background: Gender differences exist in Parkinson's disease (PD), both in clinical manifestations and response to medical treatment. We investigated whether gender differences occur in the clinical characteristics of patients selected for bilateral subthalamic nucleus deep brain stimulation (STN DBS) or in the outcome when resource limits influence treatment choices made by patients. Materials and Methods: Fifty-one consecutive patients were evaluated 1 month before, and 12 months after bilateral STN DBS. All patients were rated using Unified Parkinson's Disease Rating Scale, Parkinson's Disease Quality of Life (PDQL) Scale, Addenbrooke's Cognitive Examination and Beck Depression Inventory. Results: Pre-operative characteristics did not differ between the genders except for lower doses of drugs (P = 0.03), worse emotional scores in PDQL (P = 0.01) and worse depression (P = 0.03) in women. There was no gender difference in the surgical outcome, except a lesser reduction of dopaminergic drugs in women. Depression and quality of life (QOL) improved equally well in women and men. Conclusion: Bilateral STN DBS is equally efficacious in both genders as a treatment for motor complications of PD and for improving QOL. Women are likely to be undertreated because of more severe dyskinesia and may experience less emotional well-being, and could therefore potentially benefit from earlier surgical treatment.

The Montreal Cognitive Assessment is a brief and easy screening tool for accurately testing cognitive dysfunction in Parkinson's disease. We tested its validity for use in non-English (Malayalam) speaking patients with Parkinson's disease. We developed a Malayalam (a south-Indian language) version of Montreal Cognitive Assessment and applied to 70 patients with Parkinson's disease and 60 age- and education-matched healthy controls. Metric properties were assessed, and the scores were compared with the performance in validated Malayalam versions of Mini Mental Status Examination and Addenbrooke's Cognitive Examination. The Montreal Cognitive Assessment-Malayalam showed good internal consistency and test-retest reliability and its scores correlated with Mini Mental Status Examination (patients: R = 0.70; P < 0.001; healthy controls: R = 0.26; P = 0.04) and Addenbrooke's Cognitive Examination (patients: R = 0.8; P < 0.001; healthy controls: R = 0.52; P < 0.001) scores. This study establishes the reliability of cross-cultural adaptation of Montreal Cognitive Assessment for assessing cognition in Malayalam-speaking Parkinson's disease patients for early screening and potential future interventions for cognitive dysfunction.

Recent reports of hearing impairment in Parkinson's disease (PD) have suggested that auditory dysfunction could be a non-motor manifestation of PD. These reports were based on observations of elderly patients for whom presbycusis may, to some extent, have contributed to hearing dysfunction. Therefore, we aimed to explore the auditory functions in younger patients with PD. We conducted a case-control study in a relatively younger (< 55 years of age at study time) population of PD patients and healthy volunteers to test whether auditory dysfunction is a significant non-motor dysfunction in PD. Pure tone audiometry (PTA) and brainstem evoked response audiometry (BERA) were performed in all participants. None of the patients or controls reported hearing deficits. Fifty-one patients with PD and 50 healthy volunteers who were age- and gender-matched to the patients participated. PTA-detected hearing impairment was found in 64.7% of patients and 28% of controls (p < 0.001) for both low-mid and/or high frequencies. Hearing impairment was more frequent in the younger subgroups of patients than age-matched controls, while the frequency of hearing impairment was similar in older groups of subjects. BERA was not different between patients and controls. Asymptomatic auditory dysfunction is a common non-motor manifestation of early-onset PD and more frequent in younger patients, indicating that it may be independent of aging. The mechanism underlying this dysfunction appears to be peripheral, although a central dysfunction cannot be ruled out based on the findings of this study.