Salt intake, blood pressure and cardiovascular disease mortality in England, 2003-2018

Abstract

Objectives: The aim of this study was to assess the changes in salt intake and concomitant changes in blood pressure (BP) and cardiovascular disease (CVD) mortality in England from 2003 to 2018.

Methods: National surveys and death registration data were used for the analysis of salt intake as measured by 24-h urinary sodium excretion (449-1069 participants per year), BP (2651-6738 participants per year) and CVD mortality.

Results: A decline in salt intake from 9.38 (SD 4.64) to 7.58 (3.41) g/d was observed between 2003 and 2014 ( P < 0.01), followed by an increase to 8.39 (4.13) g/d in 2018 ( P < 0.01). Similar trends in BP and CVD mortality were also observed between 2003 and 2018. SBP/DBP decreased from 125.3 (15.92)/74.48 (11.33) mmHg to 122.57 (14.92)/73.33 (10.75) mmHg between 2003 and 2014 ( P < 0.01), followed by a plateau up to 2018 [122.04 (14.64)/73.84 (10.54) mmHg, P > 0.05]. Likewise, a fall in stroke and ischaemic heart disease mortality rates was observed between 2003 and 2014, from 12.24 and 43.44 cases per 100 000, to 8.19 and 27.23 cases per 100 000 ( P < 0.01), respectively, followed by a plateau afterwards ( P > 0.05).

Conclusion: The UK salt reduction programme was initially successful in reducing population salt intake by 19% (from 9.38 g/d in 2003 to 7.58 g/d in 2014). However, in recent years, the programme stalled and thus led to an interruption in the decline of salt intake. BP and CVD mortality reduction was also interrupted when salt reduction stalled. The changes in salt intake may have played an important role in the concomitant changes in BP and CVD mortality. Urgent action is needed to reinvigorate the UK's once world-leading salt reduction programme.