Body mass index (BMI) is a value derived from the mass (weight) and height of a person. The BMI is defined as the body mass divided by the square of the body height, and is expressed in units of kg/m2, resulting from mass in kilograms and height in metres.
Life expectancy is a statistical measure of the estimate of the span of a life. The most commonly used measure is life expectancy at birth (LEB), which can be defined in two ways. Cohort LEB is the mean length of life of a birth cohort and can be computed only for cohorts born so long ago that all their members have died. Period LEB is the mean length of life of a hypothetical cohort assumed to be exposed, from birth through death, to the mortality rates observed at a given year. National LEB figures reported by national agencies and international organizations for human populations are estimates of period LEB.
Epidemiology is the study and analysis of the distribution, patterns and determinants of health and disease conditions in a defined population.
A cohort study is a particular form of longitudinal study that samples a cohort, performing a cross-section at intervals through time. It is a type of panel study where the individuals in the panel share a common characteristic.
Gerontology is the study of the social, cultural, psychological, cognitive, and biological aspects of aging. The word was coined by Ilya Ilyich Mechnikov in 1903, from the Greek γέρων (gérōn), meaning "old man", and -λογία (-logía), meaning "study of". The field is distinguished from geriatrics, which is the branch of medicine that specializes in the treatment of existing disease in older adults. Gerontologists include researchers and practitioners in the fields of biology, nursing, medicine, criminology, dentistry, social work, physical and occupational therapy, psychology, psychiatry, sociology, economics, political science, architecture, geography, pharmacy, public health, housing, and anthropology.
Men who have sex with men (MSM) are male persons who engage in sexual activity with members of the same sex. The term was created in the 1990s by epidemiologists to study the spread of disease among all men who have sex with men, regardless of sexual identity, to include, for example, male prostitutes. The term is often used in medical literature and social research to describe such men as a group for research studies. It does not describe any specific sexual activity, and which activities are covered by the term depends on context.
A multivitamin is a preparation intended to serve as a dietary supplement with vitamins, dietary minerals, and other nutritional elements. Such preparations are available in the form of tablets, capsules, pastilles, powders, liquids, or injectable formulations. Other than injectable formulations, which are only available and administered under medical supervision, multivitamins are recognized by the Codex Alimentarius Commission as a category of food.
The British Doctors' Study was a prospective cohort study which ran from 1951 to 2001, and in 1956 provided convincing statistical proof that tobacco smoking increased the risk of lung cancer.
The Framingham Heart Study is a long-term, ongoing cardiovascular cohort study of residents of the city of Framingham, Massachusetts. The study began in 1948 with 5,209 adult subjects from Framingham, and is now on its third generation of participants. Prior to the study almost nothing was known about the epidemiology of hypertensive or arteriosclerotic cardiovascular disease. Much of the now-common knowledge concerning heart disease, such as the effects of diet, exercise, and common medications such as aspirin, is based on this longitudinal study. It is a project of the National Heart, Lung, and Blood Institute, in collaboration with Boston University. Various health professionals from the hospitals and universities of Greater Boston staff the project.
The Whitehall Studies investigated social determinants of health, specifically the cardiovascular disease prevalence and mortality rates among British civil servants. The initial prospective cohort study, the Whitehall I Study, examined over 17,500 male civil servants between the ages of 20 and 64, and was conducted over a period of ten years, beginning in 1967. A second cohort study, the Whitehall II Study, was conducted from 1985 to 1988 and examined the health of 10,308 civil servants aged 35 to 55, of whom two thirds were men and one third women. A long-term follow-up of study subjects from the first two phases is ongoing.
Ralph S. Paffenbarger, Jr. was an epidemiologist, ultramarathoner, and professor at both Stanford University School of Medicine and Harvard University School of Public Health.
The Nurses' Health Study is a series of prospective studies that examine epidemiology and the long-term effects of nutrition, hormones, environment, and nurses' work-life on health and disease development. The studies have been among the largest investigations into risk factors for major chronic diseases ever conducted. The Nurses' Health Studies have led to many insights on health and well-being, including cancer prevention, cardiovascular disease, and type 2 diabetes. They have included clinicians, epidemiologists, and statisticians at the Channing Laboratory, Harvard Medical School, Harvard School of Public Health, and several Harvard-affiliated hospitals, including Brigham and Women's Hospital, Dana–Farber Cancer Institute, Children's Hospital Boston, and Beth Israel Deaconess Medical Center.
Men's health is a state of complete physical, mental, and social well-being, as experienced by men, and not merely the absence of disease. Differences in men's health compared to women's can be attributed to biological factors, behavioural factors, and social factors.
The lipid hypothesis is a medical theory postulating a link between blood cholesterol levels and the occurrence of cardiovascular disease. A summary from 1976 described it as: "measures used to lower the plasma lipids in patients with hyperlipidemia will lead to reductions in new events of coronary heart disease". It states, more concisely, that "decreasing blood cholesterol [...] significantly reduces coronary heart disease".
Cognitive epidemiology is a field of research that examines the associations between intelligence test scores and health, more specifically morbidity and mortality. Typically, test scores are obtained at an early age, and compared to later morbidity and mortality. In addition to exploring and establishing these associations, cognitive epidemiology seeks to understand causal relationships between intelligence and health outcomes. Researchers in the field argue that intelligence measured at an early age is an important predictor of later health and mortality differences.
The Seven Countries Study is an epidemiological longitudinal study directed by Ancel Keys at what is today the University of Minnesota Laboratory of Physiological Hygiene & Exercise Science (LPHES). Begun in 1956 with a yearly grant of US$200,000 from the U.S. Public Health Service, the study was first published in 1978 and then followed up on its subjects every five years thereafter.
The Africa/Harvard School of Public Health Partnership for Cohort Research and Training launched in 2008, is a collaborative research project led by Principal Investigators, Dr. Hans-Olov Adami and Dr. Michelle D. Holmes. Together with research scientists, Dr. Shona Dalal and Dr. Todd G. Reid, this team represents the Harvard Coordinating Site of the Partnership with colleagues from five institutions in Nigeria, South Africa, Tanzania, and Uganda. The Africa/HSPH PaCT project plans on investigating the association of lifestyle factors and chronic disease risk in sub- Saharan Africa, through a large epidemiological cohort study that will include approximately 500,000 participants. Africa/HSPH PaCT is the first and largest cohort study conducted in sub-saharan Africa to employ mobile phone technology to follow participants and collect data. Africa/HSPH PaCT will also provide the infrastructure for capacity-building and for training a new generation of health professionals.
David John Hunter is an Australian epidemiologist and the Richard Doll Professor of Epidemiology and Medicine at Oxford Population Health. He was previously a professor in Harvard University's departments of Epidemiology and Nutrition. Hunter was associate epidemiologist, Channing Laboratory, Brigham and Women's Hospital, where he was involved with the programs in breast cancer, cancer epidemiology, and cancer genetics research teams. At Oxford he directs the Translational Epidemiology Unit and leads a collaborative project between Oxford and the Harvard T.H. Chan School of Public Health.
Employees who work overtime hours experience numerous mental, physical, and social effects. In a landmark study, the World Health Organization and the International Labour Organization estimated that over 745,000 people died from ischemic heart disease or stroke in 2016 as a result of having worked 55 hours or more per week. Significant effects include stress, lack of free time, poor work-life balance, and health risks. Employee performance levels could also be lowered. Long work hours could lead to tiredness, fatigue, and lack of attentiveness. As a result, suggestions have been proposed for risk mitigation.
Frank Erwin Speizer is an American physician and epidemiologist, currently Professor of Environmental Health and Environmental Science at Harvard T.H. Chan School of Public Health, and Edward H. Kass Distinguished Professor of Medicine at Brigham and Women's Hospital, Harvard Medical School. He is best known for his work on two major epidemiological cohort studies: the Nurses' Health Study, which explored women's illnesses and health risk factors, and the Harvard Six Cities study, which definitively linked air pollution to higher death rates in urban areas.
