Table 1.
Associations of risk factors with incident PD status
| Risk factor | Category | OR | Lower 95% CI | Upper 95% CI | P value | Likelihood ratio FDR Q |
| Family history: PD | Family history | 2.19 | 1.81 | 2.65 | 3.62E-13 | 9.78E-12 |
| Alcohol: <1 drink per week | Environmental | 1.39 | 1.24 | 1.57 | 8.96E-08 | 1.21E-06 |
| Depression | Comorbidity | 1.76 | 1.43 | 2.17 | 9.40E-07 | 8.46E-06 |
| Epilepsy | Comorbidity | 2.87 | 1.97 | 4.19 | 2.58E-06 | 1.39E-05 |
| Excessive daytime sleepiness | Prodrome | 1.33 | 1.19 | 1.50 | 2.07E-06 | 1.39E-05 |
| Smoking status: current | Environmental | 0.65 | 0.51 | 0.81 | 2.34E-04 | 0.001 |
| Smoking status: previous | Environmental | 0.88 | 0.78 | 0.98 | 2.34E-04 | 0.001 |
| Family history: dementia | Family history | 1.26 | 1.09 | 1.45 | 0.002 | 0.008 |
| Age at menarche | Early life | 0.93 | 0.88 | 0.98 | 0.010 | 0.032 |
| Diabetes | Comorbidity | 1.27 | 1.03 | 1.57 | 0.030 | 0.086 |
| Gastric ulcer | Comorbidity | 1.69 | 1.09 | 2.64 | 0.032 | 0.086 |
| Age at voice breaking: older than average | Early life | 1.01 | 0.70 | 1.45 | 0.073 | 0.156 |
| Age at voice breaking: younger than average | Early life | 1.54 | 1.09 | 2.18 | 0.073 | 0.156 |
| Family history: stroke | Family history | 1.11 | 0.99 | 1.26 | 0.075 | 0.156 |
| Head injury | Comorbidity | 2.00 | 1.03 | 3.87 | 0.064 | 0.156 |
| Childhood obesity | Early life | 1.13 | 0.97 | 1.32 | 0.132 | 0.255 |
| Hypertension | Comorbidity | 1.08 | 0.96 | 1.22 | 0.182 | 0.328 |
| Exposed to maternal smoking | Early life | 0.92 | 0.80 | 1.05 | 0.213 | 0.343 |
| Family history: depression | Family history | 1.11 | 0.94 | 1.32 | 0.216 | 0.343 |
| Anxiety | Comorbidity | 1.30 | 0.82 | 2.04 | 0.281 | 0.400 |
| Breastfed as a baby | Early life | 0.91 | 0.77 | 1.08 | 0.281 | 0.400 |
| Family history:diabetes | Family history | 0.93 | 0.81 | 1.07 | 0.331 | 0.447 |
| BMI | Environmental | 1.01 | 0.99 | 1.02 | 0.363 | 0.467 |
| Age completed full time education | Early life | 0.99 | 0.96 | 1.02 | 0.403 | 0.473 |
| Right-handed | Early life | 0.92 | 0.77 | 1.11 | 0.398 | 0.473 |
| Migraine | Comorbidity | 1.14 | 0.80 | 1.62 | 0.488 | 0.549 |
| Constipation | Prodrome | 1.28 | 0.32 | 5.13 | 0.741 | 0.789 |
| Pesticide exposure | Environmental | 1.12 | 0.55 | 2.30 | 0.759 | 0.789 |
| Cups of coffee per day | Environmental | 1.00 | 0.97 | 1.03 | 0.918 | 0.918 |
Output is from logistic regression models of the form PD status ~Age+Sex+Deprivation+Ethnicity+risk factor. P values are asymptotic p values calculating from the z statistic. Likelihood ratio test Q values represent the local FDR-corrected p value for the likelihood ratio test comparing model fit with and without the risk factor term (ie, compared with a null model consisting only of the covariates age, sex, ethnicity and deprivation).
BMI, body mass index; FDR, false discovery rate; PD, Parkinson’s disease.