Getting a plus powered lens before 40yr of age is called premature presbyopia . Using spectacles does not mean that vision will be lost , Its just an aid to improve or treat your husband symptoms.
Next Steps
Visit an ophthalmologist for proper guidance and treatment.
Health Tips
1. Buy a good anti glare blueray protective glasses.
2. Take break from digital screen every 20min for 20 sec
3 . Blink frequently while working on screen
4. You can use artificial eye drops for burning sensation