Table 1 Characteristic of prospective cohort studies included in the meta-analysis.
Author, yearCountryStudy nameAge, median (range), yearsNo. of casesCohort of size, genderOutcome/end points ascertainmentCause of deathMeassure of tooth lossDuration of follow- up (years)Adjustment for covariates
Hamalainen, 2003 [41]FinlandThe Evergreen project (Jyvaskyla, Finland)NA (80–90)150226, male and femaleMortality data were received from the population register.All-cause deathClinical measured number of teeth10Adjusted for the general health variables.
Tuominen, 2003 [26]FinlandMini-Finland Health SurveyNA (30–69)3196527, male and femaleRecorder linkage with the national mortality register.CHDClinical measured number of teeth12Adjusted for age, other oral health indicators, level of education, hypertension, hypercholesterolemia, smoking, and diabetes.
Hung, 2004 [18]USAHealth Professionals Follow-up Study (HPFS) and Nurses’ Health Study (NHS)NA (40–75)720100381, male and femaleThe mortality records obtained from hospital records, autopsy report, or death certificate.CHDSelf-reported number of teeth12 (HPFS), 6 (NHS)Adjusted for age (5-year categories), smoking (never, former, current, 1–14, 15–24, and ≥25 cigarettes per day), alcohol consumption (5 categories), body mass index (5 categories), physical activity (5 categories), family history of myocardial infarction, multivitamin supplement use, vitamin E use, history of hypertension, diabetes, and hypercholesterolemia in both cohorts and professions for men only, and for women only, menopausal status and hormone use.
Cabrera, 2005 [12]SwedenA prospective population study of women from GothenburgMiddle-aged Swedish women2661462, femaleInformation on mortality was obtained from death certificates.CVD, all-cause deathClinical measured number of missing teeth24Adjusted for age and husband’s occupation, education, and income.
Tu, 2007 [25]UKGlasgow Alumni cohortNA (≤30) (age at the entry of the study)163512223, male and femaleRecorder linkage with the national health service central register.CVD and CHD, stroke, cancer, All-casue mortalityClinical measured number of teeth57Adjusted for age at examination, sex, father’s socioeconomic position (derived from father’s occupation), smoking status, body mass index (BMI), computed as weight divided by height squared, and systolic blood pressure, all measured in early adulthood.
Dietrich, 2008 [13]USAVA Normative Aging and Dental Longitudinal StudiesNA (21–84)1091203, maleTriennial comprehensive medical examinations with the same criteria used in the Framingham Heart Study.CHDClinical measured number of remaining teeth24Adjusted for age, body mass index, high-density lipoprotein cholesterol, total cholesterol, triglycerides, hypertension, mean systolic and diastolic blood pressure, diabetes mellitus, fasting glucose, smoking, alcohol intake, occupation and education, income, and marital status.
Padilha, 2008 [22]USABaltimore Longitudinal Study of Aging (BLSA)Survivors: 48.38 ± 14.52; decedents: 71.31 ± 11.10198500, male and femaleMortality ascertainment of inactive participants was done by telephone follow-up, correspondence from relatives, and annual searches of the National Death Index.All-cause deathClinical measured number of teeth13.7 (164 months)Adjusted for age, sex, self-rated health, glucose at 2 h, high-intensity physical activity, total physical activity, abdominal skinfold thickness, smoking, white blood cell count, myocardial infarction, cancer, clinical diabetes, angina, transitory ischemic attack, number of teeth, frequency of brushing teeth, difficulty of chewing, number of teeth with cervical caries, number of teeth with coronal caries, DMFT (sum of the number of decayed, missing and filled teeth), average Periodontal Index, and average Gingival Index.
Österberg, 2008 [21]SwedenOdontological cohorts (Goteborg)70 (NA)10031803, male and femaleMortality data were collected from the national Swedish health registers.All-cause deathClinical measured number of missing teeth18Adjusted for health factors, socio-economic and lifestyle factors.
Holmlund, 2011 [16]Sweden51.7 ± 13.8 (20–89)6297674, male and femaleThe date and cause of death were obtained from the Swedish Cause of Death Register using the unique personal number of all participating individuals.CVD, CHD, Stroke, and all-cause deathClinical measured number of remaining teeth12Adjusted for age, gender, and smoking.
Paganini-Hill, 2011 [23]USAThe Leisure World Cohort Study81 (52–105)47535611, male and femaleSearch of government al and commercial death indexes and ascertainment of death certificates.All-cause deathSelf-reported number of natural teeth9Adjusted for age at entry, smoking, alcohol, caffeine, active activities, other activities, body mass index, high blood pressure, angina, heart attack, stroke, diabetes, rheumatoid arthritis, and cancer.
Hayasaka, 2013 [15]JapanThe Ohsaki Cohort 2006 StudyNA (≥65)236221730, male and femaleInformation on mortality was obtained from Ohsaki City government.All-cause deathSelf-reported number of teeth4Adjusted for age, sex, education level, smoking, alcohol drinking, body mass index, time spent walking daily, medical history, psychological distress, and energy and protein intake.
Schwahn, 2013 [24]GermanThe Study of Health in Pomerania (SHIP)63.6 (NA)3621803, male and femaleInformation was collected from population registries and local health authorities.CVD, all-cause deathClinical measured number of unreplaced teeth9.9Adjusted for age (restricted cubic splines), sex, education, marital status, partnership, smoking, risky alcohol consumption, physical activity, diagnosed diabetes mellitus, and obesity.
Ando, 2014 [11]JapanThe Iwate-KENCO studyNA (40–79)4557779, maleDates of death and relocation from the study area were annually or biannually confirmed by investigators who reviewed population -register sheets at each local government office.CVD, cancer, all-cause deathSelf-reported number of teeth5.6Adjusted for age, BMI, SBP, TC, HDLC, HbA1c, smoking status, alcohol drinking status, and education level.
Janket, 2014 [19]FinlandKuopio Oral Health and Heart (KOHH) study60 (NA)124506, male and femaleThe mortality records obtained from the Finnish Death Registry.CVD, all-cause deathClinical measured number of teeth15.8Adjusted for age, sex, smoking (never, past, and current), hypertension, diabetes, total/HDL cholesterol ratio and education (in years), CRP ≥ 3 mg/l, fibrinogen > median (3.0 g/l).
Liljestrand, 2015 [20]FinlandThe National FINRISK 1997 StudyNA (25–74)8918446, male and femaleRecord linkage with the National Hospital Discharge register for hospitalizations and the disease-associated drug reimbursement records from the Social Insurance Institution of Finland.All-cause deathClinical measured number of missing teeth13Adjusted for age, sex, systolic blood pressure, total cholesterol (log), high-density lipoprotein (HDL) cholesterol (log), education (3 categories), smoking (yes/no), treated systolic blood pressure (medication within 0–7 days, yes/no), existing DM, and a geographic variable (east/west).
Hu, 2015 [17]China (Taiwan)A government-sponsored, annual physical examination program.73.34 ± 6.8 (≥65) (NA)353055651, male and femaleTheir mortality data were ascertained based on the national death files.All-cause deathClinical measured number of teeth6Adjusted for age, sex, marital status, education level, regular dental prophylaxis, smoking status, alcohol consumption, diabetes mellitus, hypertension, hyperlipidemia, and nonregular dental prophylaxis.
Vedin, 2015 [27]39 countries from five continents.STABILITY trial64.4 ± 9.3 (NA)112015456, male and femaleAll suspected endpoints were initially documented and reported by STABILITY study investigators and subsequently adjudicated according to pre-specified criteria by an independent clinical events committee, blinded with respect to the assigned treatment group.CVD, all-cause deathSelf-reported number of teeth3.7Adjusted for randomized treatment (darapladib or placebo), age, systolic BP, diastolic BP, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, history of diabetes, prior MI, gender, smoking status and waist hip ratio, estimated glomerular filtration rate, family history of coronary heart disease, alcohol consumption, years of education, level of physical activity and country income level.
Joshy, 2016 [6]AustraliaThe Sax Institute’s 45 and Up StudyNA (45–75)1908172630, male and femaleInformation on mortality was obtained from Centre for Health Record linkage.ALL-cause deathSelf-reported number of natural teeth left3.9Adjusted for age and sex, tobacco smoking, alcohol consumption, Australian born status, region of residence, education, health insurance, physical activity and body mass index, with missing values in covariates were coded as a separate categories (0.3%, 1.7%, 0%, 0.03%, 1.3%, 0%, 4%, and 7%, respectively).
  • Abbreviations: M, male; NA, not available; W, female.