The number of people in the UK with private health insurance rose by more than 5 per cent last year to almost 6.9 million, according to market analysts, Laing and Buisson - the highest annual growth for a decade.Combined with those people who obtain medical care benefits through schemes offered by employers, the company estimates that 12.6 per cent of the population has private health cover.Income for private health insurers increased even more sharply, rising by 10.7 per cent last year to almost£2.5bn.