While I get looking at his teeth you have to think "Holy shit this guy is going to die" but I really don't think outside of his oral health he's in really bad or failing health. I'm sure he has high blood pressure and he has that rash on his foot but what else is wrong with him physically?
The Haloalkanes in the duster are nasty shit, they are highly toxic to the liver (along with all the alcohol he drinks) which is my bet as to what finally finishes him off. They also cause brain damage with prolonged use - he's been spotted having what look a lot like micro-seizures on stream, where he just freezes up for a second or two. That ain't good, though it's very hard to tell whether and when it would kill him before his liver does, depends on what parts of his brain are damaged and how much. Thing is, brain damage like that is near-irreversible, he's stuck with seizures now and they will only get worse the longer he uses duster. They're also potent carcinogens.
Ways Cobes could die suddenly at any moment:
- Grand Mal seizure, especially if it causes inhalation of vomit or causes him to hit his head on something as he falls down.
- Stroke, the blood vessels in his brain are likely damaged by the duster.
- Aneurysm, see above.
- Hypoxia from inhalant overdose. This is especially dangerous as he may not see it coming. Our drowning/suffocating response is not caused by low O2, it's caused by high CO2, so anything that displaces oxygen in the blood without raising CO2 (many chemicals in inhalants do this) can knock you out then kill you without you knowing anything is wrong (this is why Carbon Monoxide is so dangerous, same mechanism).
- Serious food poisoning such as botulism from his mead.
- Heart attack during inhalation (haloalkanes interfere with your adrenaline response and can cause it to surge)
- Sepsis from uncontrolled dental abscess or other infection.
- Acute alcohol toxicity (actually dying from inhalant toxicity is rare as you pass out before you get a fatal dose, though this can kill you in other ways, see above)
- Good ol' passing out and inhaling his own vomit. Jimi Hendrix would be proud
Ways Cobes could die in the long run:
- Liver failure
- Nervous system damage (brain/nerves too damaged to operate his heart and lungs)
- Cancer (any of a hundred different kinds given the hideous shit he exposes himself to)
- Gastrointestinal failure causing malnutrition
Ways Cobes could be so severely disabled he will need to be in a home for the rest of his life:
- Parkinsonism (long-term solvent abuse can bring on Parkinson's disease symptoms even if you don't have the genes for it)
- Stroke (look at Jack Scalfani)
- Uncontrollable epilepsy from inhalant-induced brain and nervous system damage
- Permanent brain damage from Grand Mal seizure, infarct or aneurysm
- Gastric failure (such as from botulism or other serious food poisoning) necessitating a feeding tube and/or colostomy
- COPD or emphysema from lung damage from both smoking and inhaling
- Diabetes
That's just what I thought of just now. There's probably many, many more that I overlooked.