People with a weak grip are more likely to have a heart attack or stroke, and more likely to die of heart problems, the study in the Lancet found.
The study authors, who followed almost 140,000 people for four years, say that testing grip would be a useful low-cost screening tool for doctors.
‘Grip strength could be an easy and inexpensive test to assess an individual's risk of death and cardiovascular disease,’ said lead author Dr Darryl Leong from McMaster University, Canada.
Men from high-income countries had an average grip strength of 38.1kg, and women 26.6kg.
Every 5kg decline in grip strength was linked to a 17% increased risk of dying from heart problems, 9% higher stroke risk, and 7% higher heart attack risk.
The effect was seen across people in 17 countries of different ages, backgrounds and health conditions.
The researchers do not yet know how grip and heart problems may be related but said that weak grip indicates reduced muscle strength, which could signify underlying health problems.
‘Further research is needed to establish whether efforts to improve muscle strength are likely to reduce an individual's risk of death and cardiovascular disease,’ Dr Leong said.