Leprosy Mailing List – June 25, 2015
Ref.: (LML) Disability Adjusted Life Years (DALYs)
From: Joel Almeida, Kochaikanal, India
Dear Pieter,
Good to renew contact with so many people from the world of leprosy work. LML is great: like a perpetual international congress, with instant peer review. Congratulations to you and all the team behind LML.
DALYs (disability-adjusted life years) may be better understood by asking the question: What is the difference in health status between an unemployed person who is in perfect health and an unemployed person who has the disfiguring sequelae of leprosy? Only one of them has a health loss. DALYs measure health loss.
DALYs lost to the sequelae of leprosy have always been calculated and reported in the GBD (global burden of disease) reports. These reports began in the 1990s.
DALY calculations in the early 2000s vastly under-estimated the stream of health losses attributable to leprosy. A great leap forward was made by GBD 2013 (Global Burden of Disease reports, 2013 update). This refused to treat people disfigured or disabled by leprosy as if they were in perfect health. However, even GBD 2013 shows a serious under-estimate of DALYs lost to leprosy. That is because it has overlooked relevant information. The oversight can easily be corrected.
DALYs, augmented by cost-effectiveness analysis, are the principal criterion by which disease control priorities are decided. DALY under-estimates lead to under-investment in leprosy work. As a consequence, persons at risk of leprosy and its sequelae suffer unnecessarily. They are deprived of cost-effective interventions that could prevent or repair health losses. One example is the failure to monitor nerve function in MB (multibacillary) patients during the first 2 years after the start of MDT (multi-drug therapy). This is likely to leave hundreds of thousands newly disabled over the next 10 years; owing to delayed or absent anti-inflammatory treatment for the “silent” neuritis which occurs despite MDT. Correct estimation of DALYs can expand the financial “cake” available to prevent or repair health losses from leprosy.
DALY calculations for leprosy in a defined geographical area require us to assess
1) The frequency and type of disfiguring or disabling sequelae among all persons disabled by leprosy (or a random sample thereof)
2) The “disability weight” of these sequelae, relative to 100% disability (which is death).
The health sequelae attributable to leprosy include visible deformities, loss of motor function, impaired vision, emotional disorders etc. The observed disabilities can be mapped against the disability weights for a range of sequelae, as given in the GBD reports. This procedure enables the summary disability weight to be calculated and reported for individuals and groups.
This is what the world means when it refers to the burden of disease: health loss owing to the sequelae of a disease. For the sake of people at risk of leprosy and its sequelae, we need to catch up with the rest of the world. Even now, we score “own goals” (a soccer term) every time we refer to “burden of disease” in a way that is different from the established DALY calculation.
The more reports we have of the frequency and type of disfiguring or disabling sequelae among all persons disabled by leprosy, and DALY loss, from different geographical areas, the sooner we will reverse the neglect of leprosy. It is neglect which we have brought upon ourselves, and we can reverse it simply by reporting DALY losses in the way that the rest of the world does.
A full description of DALYs and YLD (years lost to disability) can be found in the series of GBD 2013 papers which appeared in The Lancet.
Two clarifications in response to a comment I received about mobile leprosy workers:
1. The main role of each mobile leprosy worker would be to do expert monitoring of nerve function among MB patients in a relatively vast population, during the first 2 years after starting MDT. That would enable prompt anti-inflammatory treatment for silent and other neuritis, preventing permanent disability. A considerable level of expertise and regular practice are required for competent monitoring of nerve function, and the record-keeping which enables small changes to be detected. Each mobile leprosy worker would cover a general population of hundreds of thousands (or even millions in urban areas). That would yield enough cases per worker to maintain and boost the worker’s clinical and record-keeping skills, while serving to prevent nerve damage from “silent” and other neuritis.
2. I mentioned a demonstration project for game-changing interventions. This referred to a demonstration which would interrupt the transmission of leprosy relatively rapidly, on a small island with a reasonably high incidence rate of leprosy. Active case detection, vigorous chemoprophylaxis, vaccination (new vaccines and/or BCG), MDT, monitoring of nerve function to enable prompt anti-inflammatory treatment: every tool we have and new tools we don’t yet have. Wouldn’t it be wonderful if we demonstrated zero transmission within a decade? Time is of the essence. We need to know more quickly how far we can get with the available tools all used in an integrated way: and where the gaps are. The USA has affiliated small islands with a relatively high incidence rate of leprosy. It is a mystery why US agencies (CDC Atlanta, USAID etc.) have not yet eliminated leprosy from such islands (or at least tried their best). That could change, if a coalition of US-based scientists approached the right people.
We have so many heroes and heroines in leprosy, people of integrity with high motivation to make a difference. Baba Amte and his successors are one example. Dermatologists who run skin camps to detect leprosy in a non-stigmatising way are another. Scientists who speak truth to power are another. Government officials who seek to follow the example of Mahatma Gandhi are another. Ordinary people in affluent countries who financially support life-changing leprosy work are another. Pharmaceutical firms who donate drugs (Novartis) are another. Philanthropic foundations and voluntary organisations are another. Councils of medical research and scientists are another. The list could go on and on. There is so much goodwill and motivation. We just need to get our DALYs right, reverse the under-investment in leprosy work, and we will succeed. We will achieve a world free from new disabilities of leprosy, while providing better care and more opportunities to those disfigured by leprosy.
Regards to all and goodbye for now,
Joel Almeida
LML - S Deepak, B Naafs, S Noto and P Schreuder
LML blog link: http://leprosymailinglist.blogspot.it/
Contact: Dr Pieter Schreuder << editorlml@gmail.com
