HR magazine columnist Bevan (pictured) said with 140 million days each year lost to sickness absence, at a cost of more than £13 billion, it is a problem policymakers "cannot afford to ignore".
Bevan comments come after research published by Fit for Work found the longer a patient with a disability or long-term condition remains out of work, the harder it is for them to return, which it claims leaves many long-term unemployed.
Fit for Work UK is a campaigning coalition formed in 2011 with the aim to help those with long-term conditions stay in work longer or manage their return to work.
The study found 40% of people with chronic conditions such as rheumatoid arthritis leave work within five years of diagnosis, while people with multiple sclerosis leave work on average 18 years before their colleagues.
"Any policy which hopes to support this group to enter and remain in work must include two key commitments to be successful: recognition of the relationship between health and work; and for healthcare practitioners to introduce work as a realistic possibility while treating patients," Bevan said.
"Employment has an important positive, therapeutic and economic impact on the life of an individual with a long-term illness; providing financial autonomy, self-respect, dignity, quality of life and a sense of self-worth."
Bevan said this is not a problem one political party or department can tackle alone.
"All political parties should commit to manifestos which join up health and work policies, so that people with long-term conditions can stay in and return to work as soon as they are well enough," he said.