Part 1 - Dental Health and Mortality Reference: Liu J, Zong X, Vogtmann E, Cao C, James AS, Chan AT, Rimm EB, Hayes RB, Colditz GA, Michaud DS, Joshipura KJ, Abnet CC, Cao Y. Tooth count, untreated caries and mortality in US adults: a population-based cohort study. Int J Epidemiol. 2022 Apr 7, https://doi.org/10.1093/ije/dyac072 Introduction Oral diseases, primarily dental decay, periodontal disease and subsequent tooth loss, affected more than 3.5 billion people worldwide in 2015.' Despite declines in children, oral diseases remain prevalent in US adults with stark, per- sistent socioeconomic disparities. 23 Oral diseases share risk factors such as sugar, alcohol and tobacco consumption with systemic diseases. Besides, oral pathogens, their products or pathogen- induced oral inflammatory mediators can trigger host in- flammatory responses either locally or at distant body sites." Periodontal disease, which often involves specific pathogenic bacteria," has long been associated with cardio- vascular disease (CVD)",1 and emerges as a risk factor for diabetes " and cancers." Tooth loss, an endpoint that cap- tures the cumulative lifetime history of caries and peri- odontal disease, has been linked with increased all-cause mortality whereas findings on CVD mortality were mixed. "Further, the association of tooth loss with can- cer mortality remains under-explored. Given the modifiable nature of oral diseases, understand- ing the link between the full spectrum of oral diseases and major chronic diseases/premature mortality is an unmet public health priority.' Of particular interest is untreated 1. Based on reviewing the excerpt from the Introduction, indicate at least two reasons the researchers conducted this study. (5 points)3. Based on the method described below for measuring the key exposure of interest, tooth count and untreated caries, do you expect any misclassieation? If so, indicate why and what type of miselassication would you expect. If not, indicate why not. (5 points) Assessment of tooth count and untreated caries Numbers of permanent teeth and untreated caries were evaluated during the dental examination performed by trained dentisrs {198394 and 1999-2004),\"3133 health technologists {200508)\" or dental hygienists (2009-10130 using a disposable dental mirror. The num- ber of permanent teeth, including root fragments, was determined by assessing each tooth position of the mouth with a maximum number of 23 [excluding third molars). Since prophylactic extraction of third molars! 4. Based on the methods for collecting information on other covariates described below, do you have any concerns about misclassification? If so, indicate why and what type of misclassification you would expect. If not, indicate why not. (5 points) Assessment of covariates Age, sex, race/ethnicity, family poverty income ratio (PIR; the ratio of family income to poverty guidelines), education, health and dental insurance, leisure-time physical activity and smoking status were self-reported from baseline ques- tionnaires. 'Ever smoker' included those who had smoked 100 cigarettes in their life and 'never smoker' was defined as those who had not. Pack-years were calculated as the num-Number of permanent teeth, no. (weighted %) Characteristics NHANES 1988-94 NHANES 1999-2010 25-28 25-28 No. of participants 3694 1075 8175 1186 Weighted no. of 50 553 727 10 455 924 67002 119 6374 506 6 participants Age, mean (SEI, y 42.8 (0.4) 63 (0.6) 45.5 (0.2) 63.9 (0.5) Follow-up duration, 22.7 (0.3) 15.8 (0.4) 10.5 (0.1) 9.6 10.2) mean (SE), y Female 1926 (49.2) 597 (56.1) 4036 (49.4) 649 (56.2) 2 Race Non-Hispanic White 1663 (82.1) 669 (85.6) 4278 (75.0) 671 (76.9) 2. Non-Hispanic Black 751 (6.8) 259 (8.8) 1262 (8.2) 249 (10.9) Hispanic 1154 (5.1) 109 (1.2) 2306 [12.2) 214 (7.5) Other 126 (6.1) 38 (4 5) 329 (4.7) 42 (4.8) Family poverty income ratio 0-1.30 283 (10.5) 392 (28.9) 1704 (12.3) 503 (33.7) 1.31-3.50 1554 (39.4) 542 (51.8) 2865 (31.6) 507 (44.0) 23.51 1257 (50.1) 141 (19.2) 3606 (56.1) 176 (22.3) 1: Education