In a Cox model , the association between lower UPSIT score and mortality ( hazard ratio -LSB- HR -RSB- = @ per point interval , @ % confidence interval -LSB- CI -RSB- = @-@ @ , p < @ ) persisted after controlling for age , gender , education , ethnicity , language , modified Charlson medical comorbidity index , dementia , depression , alcohol abuse , head injury , smoking , body mass index , and vision and hearing impairment ( HR = @ , @ % CI = @-@ @ , p < @ ) .