Association of visual impairment with risk for future Parkinson's disease

Association of handgrip strength and walking pace with incident Parkinson's disease

BACKGROUND

We aimed to quantify the association of handgrip strength and self-reported walking pace with incident Parkinson's disease (PD) in the general population.

METHODS

A total of 419 572 participants (54.1% females, mean age: 56.1 years [SD, 8.2]) without prior PD were included from UK Biobank. Handgrip strength was assessed by dynamometer. Walking pace was self-reported as slow, average or brisk. The study outcome was incident PD, determined by self-report data, hospital admission records or death records.

RESULTS

The mean handgrip strength was 23.5 (SD, 6.3) and 39.6 (SD, 8.9) kg for females and males, respectively. A total of 33 645 (8.0%), 221 682 (52.8%) and 164 245 (39.2%) participants reported slow, average and brisk walking pace, respectively. Over a median follow-up duration of 12.5 years, 2152 participants developed incident PD. When handgrip strength was assessed as sex-specific tertiles, compared with those in the third tertile, the adjusted hazard ratios (HRs) (95% confidence interval [CI]) of incident PD for participants in the second and first tertiles were 1.23 (1.09-1.39) and 1.60 (1.42-1.79), respectively. Compared with brisk walking pace, average (HR, 1.33; 95% CI: 1.20-1.47) or slow (HR, 1.84; 95% CI: 1.57-2.15) walking pace was associated with a higher risk of incident PD. A lower grip strength (Tertiles 1 and 2) and an average/slow walking pace accounted for 23.8% and 19.9% of PD cases, respectively. When handgrip strength and walking pace were considered together, the highest risk of incident PD was observed in participants with both lowest handgrip strength and slow walking pace (HR, 2.89; 95% CI: 2.30-3.64). Genetic risks of PD did not significantly modify the relation of handgrip strength (P for interaction = 0.371) or walking pace (P for interaction = 0.082) with new-onset PD.

CONCLUSIONS

Low handgrip strength and slow walking pace were significantly associated with a higher risk of incident PD, regardless of the individuals' genetic risk profile.

Increased end-stage renal disease risk in age-related macular degeneration: a nationwide cohort study with 10-year follow-up

Common etiologies between age-related macular degeneration (AMD) and kidney disease advocate a close link between AMD and end-stage renal disease (ESRD). However, the risk of ESRD in people with AMD was not reported. Here, we investigated the association between AMD and the risk of ESRD by using a nationwide, population-based cohort data in Korea. 4,206,862 participants aged 50 years or older were categorized by presence of AMD and visual disability. Risk of ESRD was the primary outcome. Cox regression hazard model was used to examine the hazard ratios (HRs) with adjustment for potential confounders. Stratified analyses by age, sex, baseline kidney function, and cardiometabolic comorbidities were performed. During the mean 9.95 years of follow-up, there were 21,759 incident ESRD events (0.52%). AMD was associated with 33% increased risk of ESRD (adjusted HR [aHR] 1.33, 95% confidence interval [CI] 1.24-1.44), and the risk was even higher when accompanied by visual disability (aHR 2.05, 95% CI 1.68-2.50) than when not (aHR 1.26, 95% CI 1.17-1.37). Age, baseline kidney function, and cardiometabolic comorbidities significantly interact between AMD and the risk of ESRD. Our findings have clinical implications on disease prevention and risk factor management of ESRD in patients with AMD.

Assessment of Risk Factors and Early Presentations of Parkinson Disease in Primary Care in a Diverse UK Population

IMPORTANCE

Early features of Parkinson disease (PD) have been described through population-based studies that overrepresent White, affluent groups and may not be generalizable.

OBJECTIVE

To investigate the association between risk factors and prediagnostic presentations of PD in an ethnically diverse UK population with high socioeconomic deprivation but universal access to health care.

DESIGN, SETTING, AND PARTICIPANTS

A nested case-control study was conducted using electronic health care records on 1 016 277 individuals from primary care practices in East London to extract clinical information recorded between 1990 and February 6, 2018. The data were analyzed between September 3, 2020, and September 3, 2021. Individuals with a diagnosis of PD were compared with controls without PD or other major neurological conditions.

MAIN OUTCOMES AND MEASURES

A matched analysis (10 controls matched for each patient with PD according to age and sex) and an unmatched analysis (adjusted for age and sex) were undertaken using multivariable logistic regression to determine associations between risk factors and prediagnostic presentations to primary care with subsequent diagnosis of PD. Three time periods (<2, 2-<5, and 5-10 years before diagnosis) were analyzed separately and together.

RESULTS

Of 1 016 277 individuals included in the data set, 5699 were excluded and 1055 patients with PD and 1 009 523 controls were included in the analysis. Patients with PD were older than controls (mean [SD], 72.9 [11.3] vs 40.3 [15.2] years), and more were male (632 [59.9%] vs 516 862 [51.2%]). In the matched analysis (1055 individuals with PD and 10 550 controls), associations were found for tremor (odds ratio [OR], 145.96; 95% CI, 90.55-235.28) and memory symptoms (OR, 8.60; 95% CI, 5.91-12.49) less than 2 years before the PD diagnosis. The associations were also found up to 10 years before PD diagnosis for tremor and 5 years for memory symptoms. Among midlife risk factors, hypertension (OR, 1.36; 95% CI, 1.19-1.55) and type 2 diabetes (OR, 1.39; 95% CI, 1.19-1.62) were associated with subsequent diagnosis of PD. Associations with early nonmotor features, including hypotension (OR, 6.84; 95% CI, 3.38-13.85), constipation (OR, 3.29; 95% CI, 2.32-4.66), and depression (OR, 4.69; 95% CI, 2.88-7.63), were also noted. Associations were found for epilepsy (OR, 2.5; 95% CI, 1.63-3.83) and hearing loss (OR, 1.66; 95% CI, 1.06-2.58), which have not previously been well reported. These findings were replicated using data from the UK Biobank. No association with future PD diagnosis was found for ethnicity or deprivation index level.

CONCLUSIONS AND RELEVANCE

This study provides data suggesting that a range of comorbidities and symptoms are encountered in primary care settings before PD diagnosis in an ethnically diverse and deprived population. Novel temporal associations were observed for epilepsy and hearing loss with subsequent development of PD. The prominence of memory symptoms suggests an excess of cognitive dysfunction in early PD in this population or difficulty in correctly ascertaining symptoms in traditionally underrepresented groups.