Associations between mode of travel to work and mortality

This research used data made available via the Office for National Statistics (ONS) Secure Research Service, which is being expanded and improved with ADR UK funding.

Authors: Richard Patterson, Jenna Panter (University of Cambridge), Professor Steven Cummins (London School of Hygiene & Tropical Medicine), Eszter Vamos, Professor Christopher Millett and Anthony Laverty (Imperial College London)

Date: May 2020

Research summary

Research using secure data found that physically active commute modes, particularly cycling and train use, are associated with a range of health benefits compared with car use across socioeconomic groups. Travel by foot and bicycle has been declining for four decades in England and Wales. However, the commute is still a major potential source of physical activity for many working-age people.

Policymakers can consider these findings when making decisions around transport. This research was also cited by a report for the UK Committee on Climate Change, which recommended a transport system that promotes active travel and road safety while minimising pollution.

In England and Wales, private motorised vehicles are used the most for commuting (67%), followed by public transport (18%), walking (11%), and cycling (3%). The mode of travel is patterned by socioeconomic groups, with walking and use of public transport more common among more deprived populations and car use more frequent among less deprived populations. Active travel could have the potential to offset well known health inequalities, such as differences in life expectancy and cardiovascular disease rates. However, the association between travel mode and health outcomes across socioeconomic groups has previously been poorly understood.

Previous research on the relationship between commute mode and mortality has only used data collected over a relatively short period of time. This research therefore used data from a population-based linkage study over a longer period, investigating how commute mode affects cardiovascular disease mortality, cancer mortality, all-cause mortality, and incident cancer. The large sample size and long follow-up period enabled the researchers to assess potentially differential effects across socioeconomic groups. This research was part of a £1.5 million project funded by the National Institute for Health and Care Research (NIHR).

Data used

The project accessed the Longitudinal Study through the Office for National Statistics (ONS) Secure Research Service. The Longitudinal Study contains linked census and life events data for a 1% sample of the population of England and Wales. It currently holds data relating to 1.2 million people, making it the largest longitudinal data resource in England and Wales.

The Longitudinal Study has linked records at each census since the 1971 Census, for people born on one of four selected dates in a calendar year. All information collected on the census is included, such as age, sex, marital status, and many other socio-demographic topics. This is then linked to life events data that has happened up to 2017, such as births, deaths, and cancer registrations.

DOI (Digital Object Identifier): Office for National Statistics, released 11 June 2019, ONS SRS Metadata Catalogue, dataset, ONS Longitudinal Study - England and Wales. 10.57906/z9xn-ng05

Methods used

To analyse commute mode, researchers restricted the sample to economically active people (this excludes children under 16 years old, full-time carers, and people who were retired from work). The Census asks respondents about their usual commute mode which can be selected from a list of travel modes. Researchers divided commute mode into four categories: private motorised mode (such as car or motorbike), public transport (such as bus or rail), walking, or cycling. People working from home were excluded.

Commuting by private motorised transport, public transport, walking, and cycling were compared in terms of all-cause mortality, cancer mortality, cardiovascular disease mortality, and cancer incidence. This comparison used a regression model commonly used in medical research to examine how specified factors influence the rate of an event happening at a particular point in time (Cox proportional-hazards models with time-varying covariates).

Models were adjusted for age, sex, housing tenure, marital status, ethnicity, university education, car access, population density, socioeconomic classification, Carstairs index quintile (a measure of deprivation in the local area), long-term illness, and year of entering the study. Differences across socioeconomic groups were also examined. To investigate associations between health outcomes and different forms of public transport individually, researchers carried out analysis that separated bus and rail.

Research findings

Between the 1991 Census and the 2011 Census, 784,677 individuals contributed data for at least one census and were included in the Longitudinal Study. In total, 394,746 economically active working-age individuals were available for this analysis. During the study period (from April 1991 to December 2016 [for mortality], or December 2015 [for cancer incidence]), 13,983 people died: 3,172 from cardiovascular disease and 6,509 from cancer. There were 20,980 incident cancer cases (new cases of cancer being recorded).

In adjusted models, bicycle commuting (compared with commuting by private motorised vehicle) was associated with:

• a 20% decreased rate of all-cause mortality
• a 24% decreased rate of cardiovascular disease mortality
• a 16% decreased rate of cancer mortality
• a 11% decreased rate of incident cancer.

Rail commuters (compared with those commuting by private motorised vehicle) had a 10% lower rate of all-cause mortality and a 21% lower rate of cardiovascular disease mortality, in addition to a 12% lower rate of incident cancer.

Walking to work was associated with 7% lower cancer incidence. Stratified analysis did not indicate differences in associations between socioeconomic groups.

Further findings included:

• 68% of individuals aged 30-44 years were private motor vehicle commuters compared with 61.9% of those aged 16-29 years
• People aged 16-29 years were most likely to use public transport for commuting (22.5%), whereas those aged 45-59 years were least likely to use public transport for commuting (15.7%)
• Men were more likely than women to commute by private motor vehicle (71.6% vs 58.7%) or bicycle (4% vs 2.3%), but were less likely to use public transport for commuting (15.6% vs 22.5%) or to walk (8.7% vs 16.6%)
• Participants of white ethnicity were more likely than minority ethnic groups to be private motor vehicle commuters (67.2% vs 50.9%) or bicycle commuters (3.4% vs 1.4%) and were less likely to be public transport commuters (16.9% vs 35.2%)
• People living in areas with fewer than 2,000 people per km² were more likely to be private motor vehicle commuters than those living in areas with a population density of at least 2,000 people per km² (75.3% vs 57.9%). They were also less likely to use public transport for commuting (10.6% vs 25.2%).

Research impact

Encouraging active travel has enormous potential. It can increase physical activity by embedding these behaviours into peoples’ everyday lives and is associated with a range of health benefits. When making decisions that influence people’s commuting choices, policymakers in the health sector and beyond should consider the potential impact on public health.  

This research received wide media coverage and has been cited by a report for the UK Committee on Climate Change. One of the report’s key recommendations is to develop a transport system that promotes active travel and road safety, which also minimises pollution.

Research outputs

Publications and reports

• The Lancet journal article, May 2020: Associations between commute mode and cardiovascular disease, cancer, and all-cause mortality, and cancer incidence, using linked Census data over 25 years in England and Wales: a cohort study
• Richard Patterson PhD, 2019: The Health Impacts of Public Transport Use

Blogs, news posts, and videos

• The Conversation article, May 2020: Cycling and walking to work lowers risk of cancer, heart disease and death – new research
• The Times news article, May 2020: Coronavirus: How swapping the car for a bike can reduce commuters’ risk of an early death
• INews article, May 2020: People who walk, cycle or take the train to work are less likely to die early
• Daily Mail news article, May 2020: Commuting by rail is healthier than driving and can cut the risk of an early death by 10%, new study finds
• Yahoo!life news article, May 2020: Cycling to work could ward off an early death

Presentations and awards

• Nominated for an ONS Research Excellence Awards People’s Choice Award

About the ONS Secure Research Service

The ONS Secure Reseach Service is an accredited trusted research environment, using the Five Safes Framework to provide secure access to de-identified, unpublished data. If you use ONS SRS data and would like to discuss writing a future case study with us, please ensure you have reported your outputs here: Outputs Reporting Form and get in touch: IDS.impact@ons.gov.uk.