A quarter of the population take up half of all GP appointments and hospitalisations.
New research found that more than a quarter of adults in England have more than one long-term illness such as high blood pressure or diabetes.
And the majority of GP consultations, prescriptions, and hospital admissions were associated with patients with so-called multimorbidity, according to experts.
Researchers said that NHS services designed to treat single illnesses need to be redesigned to cope with the rising tide of people with multiple long-term conditions.
The authors of the study, published in the British Journal of General Practice, point out that patients with numerous long-term conditions “often have complicated medical needs, including understanding and managing multiple illnesses and complex medication regimens”.
After analysing data on more than 400,000 GP patients in England, the researchers found that 27.2 per cent have more than one long-term condition.
Just over half of GP consultations are devoted to patients with more than one long-term health problem. And 78.7 per cent of prescriptions were given to patients with multimorbidity.
Among the patients studied, 155,488 patients (38.5 per cent) were admitted to hospital at least once during the four year follow-up period. And those with multimorbidity accounted for 56.1 per cent of these admissions.
The authors, from the universities of Cambridge, Bristol and Utah, wrote: “Essentially, one quarter of the population is accounting for more than half of health service utilisation. Multimorbidity was highly associated with increased rates of GP consultations, prescriptions, and hospitalisations, which highlights the disproportionately large demand that patients with multimorbidity place on the UK’s overburdened healthcare system.
“As the majority of healthcare encounters are now with patients with multimorbidity, all health professionals must be trained to manage the cumulative effects of more than one chronic condition.”