TABLE 2.
Factors associated with age of AD diagnosis across DS research groups in Europe.
| Model 1 * | Model 2 ** | Model 3 *** | Model 4 **** | |||||
|---|---|---|---|---|---|---|---|---|
| Variable | exp(β) (95% CI) | p‐Value | exp(β) (95% CI) | p‐Value | exp(β) (95% CI) | p‐Value | exp(β) (95% CI) | p‐Value |
| Sex | ||||||||
| Male | Ref. | Ref. | Ref. | Ref. | ||||
| Female | 0.97 (0.94‐1.00) | 0.02 | 0.98 (0.95‐1.01) | 0.11 | 0.97 (0.93‐1.00) | 0.08 | 0.97 (0.94‐1.00) | 0.03 |
| Level of ID | ||||||||
| Mild | Ref. | Ref. | Ref. | |||||
| Moderate | 1.01 (0.98‐1.05) | 0.48 | 1.01 (0.96‐1.05) | 0.79 | 1.01 (0.96‐1.06) | 0.71 | 1.01 (0.96‐1.05) | 0.82 |
| Severe | 1.02 (0.98‐1.06) | 0.39 | 1.02 (0.97‐1.07) | 0.47 | 1.01 (0.96‐1.07) | 0.68 | 1.01 (0.96‐1.06) | 0.60 |
| Country | ||||||||
| Spain | Ref. | Ref. | Ref. | Ref. | ||||
| Germany | 1.00 (0.94‐1.06) | 0.96 | 1.01 (0.94‐1.08) | 0.80 | 1.04 (0.95‐1.12) | 0.41 | ||
| France | 1.04 (1.00‐1.08) | 0.04 | 1.07 (1.02‐1.12) | 0.006 | 1.12 (1.05‐1.19) | 0.0003 | 1.08 (1.03‐1.13) | 0.003 |
| The Netherlands | 1.03 (1.00‐1.07) | 0.08 | 1.02 (0.98‐1.07) | 0.35 | 1.03 (0.98‐1.07) | 0.24 | ||
| UK | 0.96 (0.92‐0.99) | 0.03 | 0.96 (0.92‐1.00) | 0.06 | 0.99 (0.94‐1.05) | 0.77 | 0.97 (0.93‐1.02) | 0.25 |
| Sleep problems | 0.96 (0.92‐1.01) | 0.10 | 0.95 (0.90‐1.00) | 0.06 | 0.95 (0.91‐1.00) | 0.04 | ||
| Hypothyroidism | 0.98 (0.95‐1.01) | 0.17 | 0.99 (0.95‐1.02) | 0.43 | 0.97 (0.94‐1.01) | 0.12 | ||
| Epilepsy/seizures | 0.98 (0.95‐1.01) | 0.23 | 0.98 (0.95‐1.02) | 0.34 | 0.99 (0.96‐1.02) | 0.54 | ||
| Current or history of sensory problems | 1.02 (0.98‐1.06) | 0.32 | 1.03 (0.99‐1.08) | 0.17 | 1.01 (0.97‐1.05) | 0.54 | ||
| Current mental health diagnosis | 0.93 (0.89‐0.98) | 0.01 | ||||||
| Currently prescribed psychotropic medication | 1.03 (0.99‐1.08) | 0.18 | ||||||
| APOE status | ||||||||
| Non‐ε4 | Ref. | |||||||
| ε4 carriers | 0.93 (0.90‐0.97) | 0.0004 | ||||||
| e2: ε4 | 1.00 (0.93‐1.08) | 0.93 | ||||||
| Model statistics | R‐squared: 0.10, F‐statistic: 4.06 on 7 and 263 DF, p‐value: 0.0003 | R‐squared: 0.12, F‐statistic: 2.47 on 12 and 218 DF, p‐value: 0.005 | R‐squared: 0.15, F‐statistic: 2.29 on 12 and 152 DF, p‐value: 0.01 | R‐squared: 0.18, F‐statistic: 3.50 on 12 and 194 DF, p‐value: 0.0001 | ||||
Notes: Spain was used as the reference group for all models as this country had the most AD cases.
Abbreviations: ID, intellectual disabilities; APOE, apolipoprotein E.; CI, confidence intervals; UK, United Kingdom.
*Model 1 consisted of sex, level of intellectual disabilities (ID) (mild, moderate and severe) and country (Spain, Germany, France, The Netherlands and the United Kingdom).
**Model 2 consisted of the variables in Model 1 and common DS morbidities (sleep problems, hypothyroidism, epilepsy/seizures) and current or history of sensory problems.
***Model 3 included Model 2 variables, with the addition of current mental health diagnosis and psychotropic medication prescription. The inclusion of these new variables excluded The Netherlands from Model 3 as data on mental health diagnosis and medication were missing in this dataset.
****Model 4 examined the effect of APOE status on age of dementia diagnosis, similarly to the previous models, Model 4 included Model 2 variables and APOE status. Model 4 did not include Germany as APOE status was not available for participants.