Context: Fatigue is one of the most frequent nonmotor manifestations in Parkinson's disease (PD), having a major effect on quality of life but is not reported in Indian patients.
Aims: To evaluate the frequency of fatigue in a cohort of PD population and its correlation with disease.
Settings and design: Fatigue Severity Scale (FSS) was translated and validated in local vernacular language. All patients of PD visiting neurology outpatient department of a tertiary care hospital.
Subjects and methods: A total of 150 patients were screened, and 104 were included in this study. They were divided into - Group I with fatigue (score of >4 in each item) and Group II without fatigue.
Statistical analysis: Data were analyzed by SPSS software version 20.0. Spearman correlation was used to evaluate the convergent validity of the FSS-Ind score with PD-related variables. The principal components analysis was applied to detect the domain structure of the FSS.
Results: Of the total 104 patients, 68 (65.3%) patients experienced fatigue. The duration of disease was significantly more (P = 0.021) in Group I (4.39 ± 3.8 years) than in the Group II (3.13 ± 1.6 years). The severity of disease also showed a positive correlation with fatigue with 50.9% patients in H and Y stage >3 experiencing fatigue. 69.1% patients of tremor phenotype experienced fatigue as compared to 32.3% of rigid phenotype. There was no relation of fatigue with age, gender, H and Y stage, levodopa equivalent dose and mean Unified PD Rating Scale motor III score.
Conclusions: Translated version of the FSS, FSS-Ind has high internal consistency and validity which supports its application as an effective tool in detecting fatigue in patients with PD. Fatigue in PD was related to duration and phenotype of the disease.
Keywords: Fatigue; Fatigue Severity Scale; Indian; Parkinson's disease.